Latest release

Life Tables for Aboriginal and Torres Strait Islander Australians

Life expectancy estimates for Aboriginal and Torres Strait Islander people for Australia and Index of Socio-Economic Disadvantage

Reference period
2015 - 2017

Key statistics

  • Life expectancy at birth for Aboriginal and Torres Strait Islander males - 71.6 years.
  • Life expectancy at birth for Aboriginal and Torres Strait Islander females - 75.6 years.
  • Increased by 2.5 years and 1.9 years respectively since 2010-2012. 

Introduction

This publication contains life expectancy estimates for Aboriginal and Torres Strait Islander people for Australia, selected states/territory, remoteness area and SEIFA (Index of Relative Socio-Economic Disadvantage) for the period 2015-2017. These are life expectancy estimates for the Aboriginal and Torres Strait Islander population as measured in the 2016 Census and adjusted for net undercount using Post Enumeration Survey (PES) results, which may not represent all Aboriginal and Torres Strait Islander people in Australia. As such, a number of data quality issues need to be considered when reporting and interpreting Aboriginal and Torres Strait Islander life expectancy estimates presented in this release.

The standard approach to compiling life tables and resulting life expectancy estimates requires complete and accurate data on the average number of deaths that occur in a period, and reliable estimates of the population (at the mid-point of the period) exposed to the risk of dying. These data are required by age and sex, so as to calculate age-sex specific death rates. In the case of Aboriginal and Torres Strait Islander mortality estimation, this situation is less than perfect. Registration of Aboriginal and Torres Strait Islander deaths have some limitations compared to those for the entire population. In addition, a number of quality issues associated with Aboriginal and Torres Strait Islander population estimates exist. In combination, these present particular methodological challenges to compiling high quality life tables and making comparisons over time. For more information see Chapter 2: Quality issues with Aboriginal and Torres Strait Islander deaths and population data.

Reporting on life expectancy estimates in the context of other measures of progress

Changes in people's propensity to identify as Aboriginal and Torres Strait Islander between Census years have resulted in compositional changes in the Aboriginal and Torres Strait Islander population over time. This is particularly prevalent in Major Cities. Between the 2011 and 2016 Censuses, the Aboriginal and Torres Strait Islander population increased by 18.4% (100,803 people). Analysis shows that 78.6% of this increase can be explained by demographic factors, such as births, deaths and overseas migration. The remaining 21.4% (or 21,531) of the increase in Census counts that could not be explained by demographic factors can be attributed to changing propensities to identify and methodological improvements in coverage and response rates in the Census (see Census of Population and Housing: Understanding the Increase in Aboriginal and Torres Strait Islander Counts, 2016, cat. no. 2077.0).

Aboriginal and Torres Strait Islander people living in Major Cities (where most of the 2011-2016 population increase occurred) were the main contributors to intercensal increases in year 12 attainment, non-school qualifications, labour force participation and higher personal weekly income. These changes pose significant challenges in the interpretation of Aboriginal and Torres Strait Islander life expectancy estimates over time.

While the estimates in this release show a small improvement in life expectancy estimates and a reduction in the gap between 2010-2012 and 2015-2017, this improvement should be interpreted with considerable caution as the population composition has changed during this period as outlined above. This release provides information on Aboriginal and Torres Strait Islander life expectancy in different geographic areas, to assist policy markers target initiatives for improved life expectancy gains.

The ABS recommends that estimates be considered in context with other health performance measures to adequately assess progress in 'Closing the Gap' measures.

Summary of headline estimates

At the national level, for 2015-2017, life expectancy at birth for Aboriginal and Torres Strait Islander males was estimated to be 71.6 years, 8.6 years less than life expectancy at birth for non-Indigenous males (80.2 years). Life expectancy at birth for Aboriginal and Torres Strait Islander females was estimated to be 75.6 years, 7.8 years less than life expectancy at birth for non-Indigenous females (83.4 years). These estimates relate to the 2016 Census-based population of Aboriginal and Torres Strait Islander people.

Since 2010-2012 when the last estimates of Aboriginal and Torres Strait Islander life expectancy were produced based on the 2011 Census, life expectancy for Aboriginal and Torres Strait Islander males and females increased by 2.5 years and 1.9 years respectively. The difference between Aboriginal and Torres Strait Islander and non-Indigenous life expectancy narrowed by 2.0 years for males and 1.7 years for females over the same period.

This slight improvement in life expectancy is consistent with the changing composition of the Aboriginal and Torres Strait Islander population between the two censuses, and in particular with stronger population growth in the Major cities, partly reflecting an increased propensity to identify as Aboriginal and Torres Strait Islander in these areas.

Use of Aboriginal and Torres Strait Islander life tables

Estimates of life expectancy at birth for Aboriginal and Torres Strait Islander Australians are commonly used as a measure for assessing Aboriginal and Torres Strait Islander population health and disadvantage to progress national 'Closing the Gap' targets.

The life tables in this release will enable the construction of Australian Bureau of Statistics (ABS) estimates and projections of the Aboriginal and Torres Strait Islander population of Australia for the period 2006 to 2031. These data are produced using the cohort-component method, in which assumptions made about levels of mortality, fertility and migration are iteratively applied to a base population to obtain projections of past and/or future populations.

Choice of method

Since the 2005-2007 issue of this publication, an improvement has been made to the method of calculating Aboriginal and Torres Strait Islander life tables at the Australia level. The method now takes age-specific identification rates into account when calculating the underidentification adjustment. For more information see Chapter 3: Data linkage to derive Aboriginal and Torres Strait Islander deaths identification rates.

However, this method could not be used for state and territory life tables due to insufficient sample from the Post Enumeration Survey to accurately calculate age-specific identification rates. The estimates for New South Wales, Queensland, Western Australia and the Northern Territory were therefore calculated without an age-specific adjustment, and followed the same methodology that was used for the 2005-2007 and 2010-2012 life tables. Due to the different methodologies, life expectancy estimates for these states and one territory are not directly comparable with the headline estimates for Australia, which used an age-specific adjustment. Comparable Australia level life tables have been calculated without an age-specific adjustment to enable national, state and territory and remoteness area comparisons.

These methods are very similar and both have two key features. First, the use of data linking enables direct calculation of identification rates. Second, by aligning the deaths data to the population estimates derived from the 2016 Census and Post Enumeration Survey the methodology ensures consistency between the numerator (that is, estimates of deaths) and the denominator (estimates of population at risk).

For completeness, a number of alternative approaches to adjust for underidentification of Indigenous status in deaths data and the resulting life expectancy estimates are presented in Appendix 2: Alternative approaches to adjust deaths. Assessment of the various alternatives showed that on balance, the same method as used for 2010-2012 and 2015-2017 life expectancy estimates was the best choice.

Life tables for Australia (headline and comparison estimates), New South Wales, Queensland, Western Australia and the Northern Territory are presented in Chapter 4: Life tables. Due to the relatively small number of Aboriginal and Torres Strait Islander deaths in Victoria, South Australia, Tasmania and the Australian Capital Territory, it is not currently possible to construct reliable individual life tables for these states and territory.

Life expectancy estimates in this publication refer to the average number of additional years a person of a given age and sex might expect to live if the age/sex-specific death rates for 2015-2017 were to continue throughout his/her lifetime.

Life expectancy may be compiled for any particular age or age group, thus, life expectancy at birth refers to the average number of years a group of new-born babies could expect to live, if they experienced the 2015-2017 death rates throughout their lifetimes. This does not equate to the number of years of life any one person or group of persons will actually live.

Life expectancy at birth of Aboriginal and Torres Strait Islander Australians

Table 1.1 presents life expectancy at selected ages for Aboriginal and Torres Strait Islander and non-Indigenous Australians. At all ages, for both males and females, life expectancy for Aboriginal and Torres Strait Islander Australians is lower than for non-Indigenous Australians.

1.1 Life expectancy at selected ages, Australia(a) - 2015-2017(b)

 LIFE EXPECTANCY 
 Aboriginal and
Torres Strait Islander
Non-IndigenousTotalDifference between
non-Indigenous and
Aboriginal and
Torres Strait Islander
life expectancy(c)
 yearsyearsyearsyears
MALES
0
71.6
80.2
80.0
8.6
1
71.1
79.4
79.2
8.3
5
67.2
75.5
75.3
8.3
25
47.9
55.8
55.7
7.9
50
26.7
32.1
32.0
5.4
65
15.8
19.0
18.9
3.1
85
4.4
4.7
4.7
0.3
FEMALES
0
75.6
83.4
83.2
7.8
1
75.2
82.6
82.5
7.5
5
71.2
78.7
78.5
7.5
25
51.7
58.9
58.7
7.2
50
29.0
34.6
34.5
5.6
65
17.1
20.8
20.7
3.7
85
4.5
4.8
4.8
0.3
DIFFERENCE BETWEEN MALES AND FEMALES
0
-4.0
-3.2
-3.3
. .
1
-4.0
-3.2
-3.2
. .
5
-4.0
-3.2
-3.2
. .
25
-3.8
-3.0
-3.1
. .
50
-2.3
-2.5
-2.5
. .
65
-1.2
-1.8
-1.8
. .
85
-0.1
-0.1
-0.1
. .
. . not applicable
a. These life expectancy estimates are calculated taking age-specific identification rates into account.
b. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
c. Differences are based on unrounded estimates.
 

Ratio of mortality rates

Life expectancy estimates reflect the rates of mortality at different ages within a population. Graph 1.2 illustrates the differences in mortality rates for Aboriginal and Torres Strait Islander and non-Indigenous Australians for 2015-2017.

For males, the largest differences were in the 40-44 year and 45-49 year age groups, where mortality rates for Aboriginal and Torres Strait Islander males were around four times higher than rates for non-Indigenous males. For females, the largest differences were in the 30-34 year and 35-39 year age groups, where mortality rates for Aboriginal and Torres Strait Islander females were over four times higher than rates for non-Indigenous females.

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  1. Ratio of Aboriginal and Torres Strait Islander mortality rate (qx) to non-Indigenous mortality rate.
  2. Headline estimates for Australia are calculated taking age-specific identification rates into account.
  3. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
     

State and territory life expectancy at birth

State and territory estimates are calculated on a different methodological basis to the headline Australia estimates (at which level it is possible to account for differing rates of mortality for different age groups). For this reason, a comparable Australia level series has been calculated without an age-specific adjustment and is included in the table below. Life expectancy at birth for people differs across the four states and territory for which estimates could be produced. For Aboriginal and Torres Strait Islander males, life expectancy at birth was highest in Queensland (72.0 years) and lowest in the Northern Territory (66.6 years). A similar pattern exists for Aboriginal and Torres Strait Islander females, with the highest life expectancy at birth in Queensland (76.4 years) and the lowest in the Northern Territory (69.9 years).

Differences in life expectancy at birth estimates between Aboriginal and Torres Strait Islander and non-Indigenous Australians were largest for males in Western Australia (13.4 years lower) and for females in the Northern Territory (12.8 years lower).

1.3 Life expectancy at birth, Indigenous status - 2015-2017(a)

 LIFE EXPECTANCY AT BIRTH 
 Aboriginal and
Torres Strait Islander
Non-IndigenousTotal(b)Difference between
non-Indigenous and
Aboriginal and
Torres Strait Islander
life expectancy at birth(c)
 yearsyearsyearsyears
MALES
NSW
70.9
80.2
80.0
9.4
Qld
72.0
79.8
79.6
7.8
WA
66.9
80.3
79.9
13.4
NT
66.6
78.1
75.3
11.5
Aust.(d)(e)
70.0
80.2
80.0
10.3
FEMALES
NSW
75.9
83.5
83.3
7.6
Qld
76.4
83.2
83.0
6.7
WA
71.8
83.8
83.4
12.0
NT
69.9
82.7
78.7
12.8
Aust.(d)(e)
74.4
83.5
83.2
9.0
DIFFERENCE BETWEEN MALES AND FEMALES
NSW
-5.0
-3.3
-3.3
. .
Qld
-4.4
-3.4
-3.4
. .
WA
-4.9
-3.5
-3.6
. .
NT
-3.2
-4.6
-3.4
. .
Aust.(d)(e)
-4.5
-3.2
-3.3
. .
. . not applicable
a. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
b. Estimates of life expectancy at birth for the total population presented in this release differ from estimates in Life Tables, States, Territories and Australia, 2015-2017 (cat. no. 3302.0.55.001). See paragraph 24 of the Methodology for more information.
c. Differences are based on unrounded estimates.
d. These life expectancy estimates are calculated without taking age-specific identification rates into account.
e. Includes all states and territories
 
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  1. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
  2. These estimates are not the headline estimates for Australia, because they are calculated without an age-adjustment, but are provided to enable effective comparisons with the state and territory, and remoteness area estimates.
  3. Includes all states and territories.
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  1. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
  2. These estimates are not the headline estimates for Australia, because they are calculated without an age-adjustment, but are provided to enable effective comparisons with the state and territory, and remoteness area estimates.
  3. Includes all states and territories.
     

Confidence intervals for Aboriginal and Torres Strait Islander life expectancy

Life expectancy estimates are presented together with their 95% confidence intervals below, to highlight that estimates have a margin of error attached to them. The 95% confidence interval indicates a range of values in which users can be 95% certain that the true life expectancy estimates lie within the interval. If the confidence intervals of two estimates do not overlap, then the estimates are statistically significant at 95% confidence level.

See Appendix 1, table A1.1 for a comparison of life expectancy estimates and associated confidence intervals from 2010-2012 to 2015-2017.

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  1. Estimates are statistically significant at 95% confidence level if their confidence intervals do not overlap.
  2. Significantly different from 2010-2012 estimate at 95% confidence level.
  3. These life expectancy estimates are calculated without taking age-specific identification rates into account.
  4. Includes all states and territories.
  5. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2010-2012 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2011 based on the 2011 Census.
  6. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
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  1. Estimates are statistically significant at 95% confidence level if their confidence intervals do not overlap.
  2. Significantly different from 2010-2012 estimate at 95% confidence level.
  3. These life expectancy estimates are calculated without taking age-specific identification rates into account.
  4. Includes all states and territories.
  5. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2010-2012 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2011 based on the 2011 Census.
  6. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
     

Improvement in life expectancy during 2010-2012 and 2015-2017

During the five-year period from 2010-2012 to 2015-2017, Aboriginal and Torres Strait Islander life expectancy at birth estimates for Australia (headline) increased by 2.5 years for males and 1.9 years for females.

The largest improvement was in Queensland (3.3 years for males and 2.0 years for females), followed by the Northern Territory (3.2 years for males and 1.2 years for females) and Western Australia (1.9 years for males and 1.7 years for females). The lowest improvement was in New South Wales (0.4 years for males and 1.3 years for females). While Aboriginal and Torres Strait Islander life expectancy increased in all states/territory for which estimates were produced, increases were only statistically significant for males in Queensland, and both males and females at the Australia comparison level.

Life expectancy by remoteness areas and SEIFA

Due to insufficient data for some RAs to be published individually, particularly at lower ages, the ABS has produced life expectancy at birth for only three categories of remoteness. These are Major Cities, Inner Regional and Outer Regional combined and Remote and Very Remote combined. Remoteness categories were grouped together according to the similarity of their mortality characteristics. Similarly, for life expectancy estimates by SEIFA (Index of Relative Socio-Economic Disadvantage), the two least disadvantaged quintiles have been grouped together due to insufficient data.

Life expectancy was significantly lower for both Aboriginal and Torres Strait Islander males and females in Remote and Very Remote areas combined (65.9 and 69.6) than for those who lived in Major Cities (72.1 and 76.5 respectively). The difference between life expectancy estimates for the Aboriginal and Torres Strait Islander and the non-Indigenous populations was also more marked in these remote and very remote areas (13.8 years for males and 14.0 years for females) than in Major Cities (8.6 years and 7.2 years respectively).

This is consistent with the estimates presented in table 1.10 which show that Aboriginal and Torres Strait Islander people living in the most disadvantaged areas, a higher proportion of whom were living in remote Australia, have the lowest life expectancy (68.2 years for males and 72.8 years for females. This represented 41% of Aboriginal and Torres Strait Islander males and females, a third of whom lived in Remote and Very Remote areas. This compared with a life expectancy at birth estimate of 77.9 years for non-Indigenous males and 82.0 years for non-Indigenous females living in areas in the most disadvantage quintile, which represented around 17% of non-Indigenous males and females, of whom 2% were living in Remote and Very Remote areas.

1.8 Life expectancy at birth, Remoteness Areas - 2015-2017(a)(b)

 Aboriginal and
Torres Strait Islander
Non-IndigenousTotalDifference between
non-Indigenous and
Aboriginal and
Torres Strait Islander
life expectancy at birth(c)
MALES
Major Cities
72.1
80.7
80.6
8.6
Inner and Outer Regional
70.0
79.1
78.7
9.1
Remote and Very Remote
65.9
79.7
76.3
13.8
FEMALES
Major Cities
76.5
83.7
83.6
7.2
Inner and Outer Regional
74.8
82.8
82.5
8.0
Remote and Very Remote
69.6
83.6
79.6
14.0
DIFFERENCE BETWEEN MALES AND FEMALES
Major Cities
-4.4
-3.0
-3.1
. .
Inner and Outer Regional
-4.8
-3.7
-3.8
. .
Remote and Very Remote
-3.8
-3.9
-3.3
. .
. . not applicable
a. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
b. These life expectancy estimates are calculated without taking age-specific identification rates into account.
c. Differences are based on unrounded estimates.
 
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  1. Estimates are statistically significant at 95% confidence level if their confidence intervals do not overlap.
  2. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
  3. These life expectancy estimates are calculated without taking age-specific identification rates into account.
  4. Difference between male and female estimates in 2015-2017 are statistically significant at 95% confidence level.
     

1.10 Life expectancy at birth, Indigenous status and sex by Index of Relative Socio-economic Disadvantage(a) - 2015-2017(b)

 Aboriginal and Torres Strait Islander
Australians
Non-Indigenous Australians
 Life expectancy% of population in this quintile% of people in this
quintile living in
Remote and Very Remote areas
Life expectancy% of population in this quintile% of people in this
quintile living in
Remote and Very Remote areas
Males      
Most disadvantaged 20%
68.2
40.6
32.2
77.9
17.6
2.2
Second most disadvantaged 20%
70.3
24.4
7.0
79.1
19.1
2.5
Middle 20%
69.9
18.0
15.2
80.4
21.3
2.4
Least disadvantaged 40%
72.4
17.0
5.5
81.7
42.0
0.6
Females      
Most disadvantaged 20%
72.8
41.3
32.2
82.0
17.4
1.7
Second most disadvantaged 20%
75.5
24.7
6.5
82.7
19.1
2.2
Middle 20%
74.3
18.2
15.9
83.5
21.2
2.2
Least disadvantaged 40%
76.6
15.8
5.4
84.4
42.3
0.4
a. These life expectancy estimates are calculated without taking age-specific identification rates into account.
b. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
 
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  1. Estimates are statistically significant at 95% confidence level if their confidence intervals do not overlap.
  2. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
  3. These life expectancy estimates are calculated without taking age-specific identification rates into account.
  4. Difference between male and female estimates in 2015-2017 are statistically significant at 95% confidence level.

Comparison with AIHW estimates

In 2017, the Australian Institute of Health and Welfare (AIHW) released a report on Aboriginal and Torres Strait Islander life expectancy estimates for 2011-2015. Like the ABS, the AIHW also compiled life expectancy estimates through a data linking process. However, the AIHW linked registered deaths with Aboriginal and Torres Strait Islander death records from three alternative data sources. These data sources were Residential Age Care Dataset, National Hospital Morbidity Database and National Perinatal Data Collection.

The AIHW study produced Aboriginal and Torres Strait Islander life expectancy at birth of 70.1 years for males and 74.5 years for females for the period 2011-2015 (AIHW, 2017). These estimates are 1.5 years and 1.1 years lower than the ABS estimates of 71.6 and 75.6 years for males and females respectively for the period 2015-2017. The reasons for this difference could be due to a range of differences in methodologies and reference periods between the ABS and AIHW studies. It is important to note that quality issues are associated with estimates produced by both agencies.

Quality issues with Aboriginal and Torres Strait Islander deaths and population data

The standard approach to compiling life tables and resulting life expectancy estimates requires complete and accurate data on the average number of deaths that occur in a period, and reliable estimates of the population (at the mid-point of the period) exposed to the risk of dying. These data are required by age and sex, so as to calculate age-sex specific death rates.

In the case of Aboriginal and Torres Strait Islander mortality estimation, this situation is less than perfect. Information on death registrations of Aboriginal and Torres Strait Islander Australians has limitations and a number of quality issues associated with Aboriginal and Torres Strait Islander population estimates exist. In combination, these present particular methodological challenges to compiling high quality life tables and making comparisons over time.

The following chapter discusses the data challenges associated with death registrations of Aboriginal and Torres Strait Islander Australians and Aboriginal and Torres Strait Islander population estimates in more detail.

Deaths of Aboriginal and Torres Strait Islander Australians

The first component necessary for the compilation of life tables as measured in the Census and adjusted for net undercount using in the Post Enumeration Survey for Aboriginal and Torres Strait Islander Australians is information on all Aboriginal and Torres Strait Islander deaths by age and sex. These are required as numerators in the calculation of age-specific death rates from which life tables are produced.

Death registrations are collected in the form of administrative data from the Registrars of Births, Deaths and Marriages in each state/territory. For all states and territories, death registration forms (DRFs) use a standard question to elicit information about a person's Aboriginal and Torres Strait Islander origin. While Australia maintains a high quality registration system of deaths, the level of Aboriginal and Torres Strait Islander identification (that is those deaths which are registered as being a person who was Aboriginal and Torres Strait Islander) varies across state/territory collections, geography and over time.

While it is considered likely that the majority of deaths of Aboriginal and Torres Strait Islander Australians are registered, some of these deaths are not identified as Aboriginal and Torres Strait Islander when they are registered. This may arise from the failure to report a person's Indigenous status on the DRF or from an incorrect identification of their Indigenous status (that is, recording non-Indigenous instead of Aboriginal and Torres Strait Islander) on the death certificate. Response to this question can be influenced by a number of factors, including the perception of why such information is required, who completes the question regarding the deceased, and personal and cultural aspects associated with identifying as Aboriginal and Torres Strait Islander. This issue remains a major challenge in developing Aboriginal and Torres Strait Islander life tables, as well as in estimating the Aboriginal and Torres Strait Islander population between Census years.

Medical Certificate of Cause of Death (MCCD)

In addition to the DRF, some states and territories have introduced the Medical Certificate of Cause of Death (MCCD) to improve Aboriginal and Torres Strait Islander identification in death records. In 2007, the MCCD was introduced in South Australia, Western Australia, Tasmania, the Northern Territory and the Australian Capital Territory. The Queensland Registry of Births, Deaths and Marriages introduced the MCCD in 2015. This resulted in a noticeable decrease in the number of deaths for which the Indigenous status was 'not stated' and an increase in the number of deaths identified as Aboriginal and Torres Strait Islander in Queensland in comparison to previous years (see table 2.1). The impact of the introduction of the MCCD in Queensland in 2015 on the 2015-2017 Aboriginal and Torres Strait Islander identification rate and life expectancy estimates is discussed in Chapter 3: Data linkage to derive Aboriginal and Torres Strait Islander deaths identification rates.

Numbers of Aboriginal and Torres Strait Islander deaths

Table 2.1 shows Aboriginal and Torres Strait Islander deaths registered from 2011 to 2017. Since 2011, the numbers of Aboriginal and Torres Strait Islander deaths registered in Western Australia and the Northern Territory have been fairly consistent. Since 2015, the number of Aboriginal and Torres Strait Islander deaths in Queensland outnumbered those in New South Wales. Queensland now has the largest number of Aboriginal and Torres Strait Islander deaths of all states and territories.

At the national level, Aboriginal and Torres Strait Islander death registrations increased from 2,558 in 2011 to 3,250 in 2017 (27%).

2.1 Registered Aboriginal and Torres Strait Islander deaths(a), state/territory of usual residence - 2011 to 2017

Year(b)New South WalesVictoriaQueenslandSouth AustraliaWestern AustraliaTasmaniaNorthern TerritoryAustralian Capital TerritoryAustralia(c)
2011
726
128
629
141
454
30
437
12
2 558
2012
635
100
678
151
466
45
539
6
2 620
2013
753
123
765
177
457
27
489
18
2 811
2014
794
139
688
169
517
31
562
13
2 914
2015(d)
822
141
842
167
511
50
537
17
3 088
2016
857
175
884
170
565
54
443
19
3 168
2017
857
186
897
222
508
52
504
22
3 250
a. Due to differing levels of identification for the states and territories and over time, care should be taken in interpreting change in numbers of deaths.
b. Registration year.
c. Includes Other Territories.
d. Queensland introduced the Medical Certificate of Causes of Death (MCCD) in 2015. This resulted in an increase in Aboriginal and Torres Strait Islander registered deaths.
 

Deaths for which Indigenous status is unknown

In addition to those deaths identified as Aboriginal and Torres Strait Islander, a number of deaths occur each year for which Indigenous status is not stated on the death registration form. In 2017, there were 971 deaths registered in Australia for whom Indigenous status was not stated, representing 0.6% of all deaths registered. While this proportion has decreased over time (from a high of 4.4% in 2001) it is very likely that some Aboriginal and Torres Strait Islander deaths are included in this category, further contributing to the uncertainty as to the true number of Aboriginal and Torres Strait Islander deaths.

Year of registration and year of occurrence of death

Deaths and related mortality statistics can be reported according to the period in which the death was registered or the period in which the death occurred. Ideally, mortality statistics should be based on year of occurrence, but ABS data, including life tables, are based on year of registration. This is due to known lags in the time between the occurrence and registration of deaths. While the majority of deaths in Australia are registered in the year they occur, some deaths registered in any given year have occurred in previous years. These delays in registration can arise due to a variety of reasons, and are more common for Aboriginal and Torres Strait Islander deaths than non-Indigenous deaths.

For example, of all non-Indigenous deaths which occurred in Australia in 2016, 95% were registered in 2016 (table 2.2). The corresponding figure was 89% for Aboriginal and Torres Strait Islander deaths.

2.2 Proportion of deaths registered in the year of occurrence - 2011 to 2016(a)

 Aboriginal and Torres Strait Islander peoplesNon-Indigenous
Year of occurrence%%
2011
86.7
95.1
2012
86.2
93.9
2013
86.9
93.4
2014
87.3
93.4
2015
88.7
94.7
2016
89.2
94.7
a. Based on deaths registered up to December 2017.
 

While the proportion of deaths registered in the same year of occurrence is lower for Aboriginal and Torres Strait Islander deaths than non-Indigenous deaths, there is little difference between the number of deaths registered in a given year and the number of deaths that occurred in the same year (see table 2.3). This is because, for each year, the number of deaths not registered in the year they occur are compensated for by deaths that occurred in previous years but were registered late (see also The Health and Welfare of Australia's Aboriginal and Torres Strait Islander Peoples, Oct 2010, cat. no. 4704.0). This indicates that Aboriginal and Torres Strait Islander deaths will produce similar death rates and life expectancy estimates for both year of occurrence and registration.

2.3 Aboriginal and Torres Strait Islander deaths by registration and occurrence - July 2011 - June 2016

 MALESFEMALES
State/territoryRegisteredOccurredRegisteredOccurred
NSW
2 036
2 046
1 787
1 785
Vic.
355
363
284
285
Qld
2 073
2 064
1 662
1 672
SA
449
443
372
377
WA
1 387
1 371
1 041
1 045
Tas.
100
101
97
97
NT
1 323
1 296
1 235
1 239
ACT
45
44
25
26
Aust.(a)
7 770
7 730
6 505
6 528
a. Includes Other Territories.

Population estimates of Aboriginal and Torres Strait Islander Australians

The second component necessary for the compilation of life tables for Aboriginal and Torres Strait Islander Australians is information on the relevant population exposed to the risk of dying; that is, the population of Aboriginal and Torres Strait Islander Australians, by age and sex. These are required as denominators in the calculation of age-specific death rates from which life tables are produced. The population used in this release are the final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census (mid-point of the 2015-2017 reference period).

Changes in the Aboriginal and Torres Strait Islander population, 2011-2016

The Census of Population and Housing is the principal source of information about Australia's population. It has been held on a five-yearly basis since 1961, with the most recent conducted in August 2016.

The Census provides the foundation from which Australia's official population figures -estimated resident population (ERP)- is calculated. The Census count of the population is adjusted for:

  • estimates of the number of people missed in the Census;
  • estimates of those counted more than once in the Census;
  • temporary visitors from overseas;
  • Australian residents temporarily overseas (RTO) on Census night; and
  • backdating from Census night to the ERP reference date of 30 June of the Census year using data on births, deaths, and interstate and overseas migration.


This process results in an estimate of Australia's total population (by age and sex) as at 30 June of the Census year. For intercensal years (that is, years other than the Census year), this Census-based ERP is incremented by adding births and net overseas migration and subtracting deaths. However, estimating the size and composition of the Aboriginal and Torres Strait Islander population is more complicated. In intercensal years this standard approach cannot be used due to the lack of sufficiently reliable data on Aboriginal and Torres Strait Islander births, deaths and migration.

For the five-yearly Census, there are a number of issues that make compilation of Aboriginal and Torres Strait Islander ERP problematic. These include:

  • undercount of the Aboriginal and Torres Strait Islander population;
  • non-response to the Indigenous status question on the Census form; and
  • unexplained increase in Aboriginal and Torres Strait Islander Census counts that can not be explained by demographic factors (such as births, deaths and overseas migration) relative to the previous Census.
     

Undercount of Aboriginal and Torres Strait Islander population

While every effort is made to ensure full coverage of people and dwellings in the Census, some people are missed (undercount) and others are counted more than once (overcount). In Australia, more people are missed from the Census than are counted more than once. The net effect of overcount and undercount is called net undercount. The ABS conducts a Post Enumeration Survey (PES) a few weeks after each Census to measure the extent of net undercount in the Census. Estimates of net undercount provide direct information on the quality of population counts in the Census, and enable the necessary adjustment or correction to be made to the raw Census counts.

In addition, for some people, the Indigenous status reported in the PES is different to the Indigenous status recorded in the Census. Accordingly, estimates from the PES include an adjustment for misclassification error.

The net undercount rate in the 2016 Census was estimated at 17.5% for the Aboriginal and Torres Strait Islander population, and 6.6% for the non-Indigenous population. Corresponding estimates for the 2011 Census were 17.2% for the Aboriginal and Torres Strait Islander population and 6.2% for the non-Indigenous population.

However, it is important to note that the net undercount rates are not strictly comparable over time due to changes in both Census and PES methodologies. The 2011 PES improved the collection of Indigenous status and also utilised the new methodology of Automated Data Linking, which resulted in better linking and matching of PES and Census records, and a better measure of net undercount. For more details on the PES and Aboriginal and Torres Strait Islander undercount, see:

Non-response to Indigenous status question on the Census form

Despite the best efforts of the Australian Bureau of Statistics (ABS) to collect complete information from all people in Australia on Census night, there will always be a group of people for whom Indigenous status is not known. While some people with an unknown Indigenous status will be Aboriginal and/or Torres Strait Islander people, and some will be non-Indigenous people, the exact proportions cannot be determined from the Census data. This complicates analysis of Census counts, given Indigenous status is not imputed within Census information, but is instead imputed later within the PES for use in producing population estimates (imputation is a statistical process for predicting values where no response was provided to a question and a response could not be derived).

The number of Census records with an unknown Indigenous status in the 2016 Census was 1,411,031 (6% of the total Census count) compared with 1,058,586 (5% of the total Census count) in 2011. The difference of 352,584 records represents a 33% increase in records with an unknown Indigenous status between the 2011 and 2016 Censuses.

The Northern Territory had the highest proportion of records with an unknown Indigenous status in 2016 (10%), followed by Western Australia and Queensland (both 7%). New South Wales, Victoria, and Tasmania each had 6% of records with an unknown Indigenous status.

There are two broad situations which result in a person's Indigenous status being unknown in the Census:

  • the returned Census form does not have a response to the Indigenous status question (known as item non-response). These persons are classified as 'responding' or 'not imputed'.
  • no Census form is received from a dwelling. These persons are classified as 'non responding' or 'not imputed'. For these persons, Indigenous status is coded to 'not stated' and data for key demographic variables such as age, sex, marital status and place of usual residence are imputed.
     

While some of these records will be for people of Aboriginal and Torres Strait Islander origin and the others for non-Indigenous origin, no imputation was made for Indigenous status in the Census file. However, for compiling Aboriginal and Torres Strait Islander ERP they are allocated as either Aboriginal and Torres Strait Islander or non-Indigenous according to the distribution of stated responses within each geographic area, age group, sex and Census form type. For more details on not stated Indigenous status and how Aboriginal and Torres Strait Islander ERP are derived, see Estimates of Aboriginal and Torres Strait Islander Australians, June 2016 (cat. no. 3238.0.55.001).

Increase in Aboriginal and Torres Strait Islander Census counts not explained by demographic factors

Changes in the Census counts of Aboriginal and Torres Strait Islander people over time that can not be explained by demographic factors, such as births, deaths and overseas migration are referred to as 'unexplainable change'. Factors that contribute to unexplainable change include: changing propensity to identify as Aboriginal and Torres Strait Islander on the Census form, as well as methodological improvements in the Census and Post Enumeration Survey over time, such as changes in coverage and response rates.

Over the past 46 years, there has been a clear upward trend in Aboriginal and Torres Strait Islander Census counts, beginning with the 1971 Census and continuing to the 2016 Census. During this time, large increases in Aboriginal and Torres Strait Islander Census counts have occurred on several occasions. Natural increase (the excess of births over deaths) can account for a proportion, but not all, of these increases, while overseas migration has had an insignificant effect on the size of the Aboriginal and Torres Strait Islander population.

Between 1991 and 1996, the Census count of Aboriginal and Torres Strait Islander people increased by 88,000 (33%). The components of this increase were estimated to be 14% due to natural increase (the impact of overseas migration negligible) and the remaining 19% due to unexplainable change.

In recent times, there has been particularly large increases between the 2006-2011 and 2011-2016 Censuses. Between 2006-2011, the Aboriginal and Torres Strait Islander population increased by 21% (or 93,000 people). Over two-thirds (65,500) of the 93,300 increase in the Census count of Aboriginal and Torres Strait Islander people between 2006 and 2011 were accounted for by demographic factors (births, deaths and overseas migration). The remaining one-third (27,800) of the increase was attributed by unexplainable change. Similarly, most (79,272 or 79%) of the 100,803 increase in the Census counts of Aboriginal and Torres Strait Islander people between 2011 and 2016 were explained by demographic factors. The remaining 21% (21,531) of the increase in Census counts was unexplainable change.

For more information on the change in Census counts of Aboriginal and Torres Strait Islander people from 2011 to 2016 see Census of Population and Housing: Understanding the Increase in Aboriginal and Torres Strait Islander Counts, 2016 (cat. no. 2077.0).

Age/sex structure

For the purposes of compiling life tables it is necessary to have accurate measures of the population according to their age and sex. It is therefore important to make some assessment of the quality of the age/sex structure of Aboriginal and Torres Strait Islander ERP for Australia and the states and territories. The age distributions of the 30 June 2011 and 2016 Aboriginal and Torres Strait Islander ERP remained more or less the same (graphs 2.4 and 2.5).

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As noted above, the Aboriginal and Torres Strait Islander population is a self-identified one and therefore it is possible for the population age distribution to change over time for reasons other than the usual demographic ones (i.e. population ageing etc). To determine if the age distribution of the 2011 and 2016 Aboriginal and Torres Strait Islander population has in fact changed, The Index of Dissimilarity, which measures the overall difference between the two age distributions (Shyrock et al., 1976:131), has been calculated.

The lower The Index of Dissimilarity values are, the more similar are the two age distributions. For two successive Census years, Aboriginal and Torres Strait Islander populations showed quite low values in comparison to its theoretical range of 0 to 100. The Index value for the Aboriginal and Torres Strait Islander population was 3.4 for males and 3.5 for females. In comparison, The Index values for the total Australian population were 2.4 and 2.5 for males and females respectively. Higher Index values for the Aboriginal and Torres Strait Islander population suggest that there has been slightly more change in the age distribution of this population between Censuses. For the states and territories, most Index of Dissimilarity values fall around or below 5.0 for both sexes except for the Australian Capital Territory for males and females, and Tasmania, for females, where the results could be less reliable due to the small size of the Aboriginal and Torres Strait Islander population used in the calculations.

2.6 Index of Dissimilarity between Aboriginal and Torres Strait Islander age structures - 30 June 2011 and 30 June 2016

 MalesFemales
State/territoryindexindex
NSW
3.5
4.1
Vic.
4.3
4.2
Qld
3.3
3.3
SA
3.3
3.4
WA
3.6
4.0
Tas.
4.9
6.7
NT
4.5
5.2
ACT
6.3
6.5
Aust.(a)
3.4
3.5
a. Includes Other Territories.
 

Conclusion

As discussed above, the required inputs for compiling Aboriginal and Torres Strait Islander life tables (that is, the average number of Aboriginal and Torres Strait Islander deaths over 2015-2017 and final 2016 Aboriginal and Torres Strait Islander mid-point population estimates for the 2015-2017 reference period) are subject to a range of data quality issues.

Aboriginal and Torres Strait Islander ERP compiled from the five-yearly Census provide a sound foundation. However, changing propensities to identify as Aboriginal and Torres Strait Islander and improvements in methodologies in the Census and Post Enumeration Survey make interpretation of changes over time in the Aboriginal and Torres Strait Islander population difficult.

In relation to Aboriginal and Torres Strait Islander death statistics, the non-reporting and/or incorrect reporting of a person's Indigenous status on the death registration form means that death rates calculated using the number of registered Aboriginal and Torres Strait Islander deaths are underestimates of the true death rates prevalent among Aboriginal and Torres Strait Islander Australians. Application of these death rates in a standard life table would result in an overestimate of Aboriginal and Torres Strait Islander life expectancy, see table A3.1 in Appendix 2Alternative approaches to adjust deaths.

For the purposes of compiling Aboriginal and Torres Strait Islander life tables, some method of adjustment is therefore required to adjust the registered number of Aboriginal and Torres Strait Islander deaths for potential underidentification in registration data. The method used by ABS to do so for the Aboriginal and Torres Strait Islander life tables is described in detail in Chapter 3: Data linkage to derive Aboriginal and Torres Strait Islander deaths identification rates.

Data linkage to derive Aboriginal and Torres Strait Islander Australians deaths identification rates

Chapter 2: Quality issues with Aboriginal and Torres Strait Islander Australians described the data required for producing Aboriginal and Torres Strait Islander life tables and life expectancy estimates, and quality issues associated with these data. This Chapter details the use of data linkage techniques to derive Aboriginal and Torres Strait Islander deaths identification rates. Specifically, it describes the Census Data Enhancement Indigenous Mortality Study, discusses the analyses undertaken and presents the results. To calculate estimates of life expectancy using direct methods, it is important to ensure that the classification of records as Aboriginal and Torres Strait Islander occurs in a consistent manner in both the numerator (deaths) and the denominator (population).

CDE Indigenous Mortality Study

The Indigenous Mortality Study was first conducted as part of the ABS Census Data Enhancement (CDE) project for the 2006 Census. It has been repeated for subsequent Censuses. Most recently, the CDE project consists of a number of studies which have brought together data from the 2016 Census of Population and Housing and other specified datasets.

For more information on the 2016 CDE project, see the paper: 'Linking Death registrations to the 2016 Census' (cat. no. 3302.0.55.004) to be released in December 2018.

The aims of the CDE Indigenous Mortality Study were to:

  • assist in understanding the differences in recording of Indigenous status between death registrations and Census data; and
  • assess the under-identification of Aboriginal and Torres Strait Islander deaths in death registrations records.
     

The CDE Indigenous Mortality Study involved linking Census records with death registration records to examine differences in the reporting of Indigenous status across the two datasets. Specifically the study linked 2016 Census records with all registered deaths that occurred from 9 August 2016 to 28 September 2017, with a slightly longer range than 12 months to allow time for all relevant deaths to be registered and processed.

In the absence of any unique identifier in the Census and deaths datasets, linking was performed using probabilistic methods. Three groups of variables, name (first name and surname), personal characteristics (date of birth, age, sex, place of birth, year of arrival and marital status), and geographic information (street number, street name, suburb, mesh block and postcode) were used to link death records to Census records. Variables common to both datasets were standardised to ensure consistent coding and formatting. The two datasets were linked in a way that was independent of reported Indigenous status so that any future analysis would not be affected by bias introduced in the linking process. For this reason, Indigenous status was not used as a linking variable.

The 2016 Death registrations to Census linkage project builds on the success of other data integration programs, incorporating enhancements from these programs.

The main enhancements implemented for the 2016 project included:

  • use of non-sequential probabilistic linking of 2016 Census data to death records (as opposed to sequential probabilistic linking used in 2011),
  • use of alternative address information from Census and Death registrations to improve linkage of records between datasets,
  • improving name repair processes, where the rarity of a name was used in evaluating the quality of links established, and
  • an enhanced clerical review strategy resulting in higher quality links.


Internationally, similar record linkage studies have been conducted in New Zealand where the 1981, 1986, 1991, 1996 and 2001 Censuses were each anonymously and probabilistically linked to three years of subsequent deaths data, allowing a comparison of ethnicity recording (Ajwani et al., 2003; Blakely et al., 2002a; Blakely et al., 2002b). Large nationally representative studies based on linked Census and deaths data have also been conducted in the United Kingdom, France, Sweden and Netherlands. The results from these studies have been used in various ways including the provision of evidence for policy decisions and the setting of policy targets for special intervention programs.

Summary results of the CDE study

The number of Census and death registration records eligible for linking and the percentage of death records linked are presented in Table 3.1. The linking process used 177,380 death records and 22,485,854 Census records. These Census counts are different from the estimated resident population, as discussed in Chapter 2: Population estimates of Aboriginal and Torres Strait Islander Australians.

Of the 177,380 death records, 159,657 (90.0%) records were linked to one of 22,485,854 eligible Census records. Of the 3,246 Aboriginal and Torres Strait Islander death records, 2,315 (71.3%) were linked.

3.1 Census and death records, Australia

DescriptionRecords
Number 
 Census records eligible for linking(a)
22 485 854
 Aboriginal and Torres Strait Islander Census records
649 171
 Records on death file(b)
177 380
 Death records linked
159 657
 Death records not linked
17 723
 Aboriginal and Torres Strait Islander records on death file(c)
3 246
 Aboriginal and Torres Strait Islander records linked(c)
2 315
Per cent 
 All death records linked
90.0
 Aboriginal and Torres Strait Islander death records linked
71.3
a. Excludes residents temporarily overseas on Census night, imputed records and Census net undercount adjustment.
b. Deaths which occurred between 09 Aug 2016 and 28 Sep 2017.
c. According to Indigenous status reported on death registration form.
 

The number and percentage of death records linked to Census records by selected characteristics of deceased persons are presented in Table 3.2. A slightly higher linkage was achieved for females (91.4%) compared with males (88.6%). The linkage rate varied considerably by age, being lowest for 0-14 year old deceased persons (63.4%). This may be due to the comparatively high Census undercount rate in this age group. The linkage rate was highest for 75 years and older deceased persons (92.9%).

3.2 Death records linked to Census records by selected characteristics, Australia

  Total death recordsLinked recordsLinked records
Reported characteristics in death registrationno.no.%
Sex   
 Males
91 143
80 796
88.6
 Females
86 237
78 861
91.4
Age (years)   
 0-14
686
435
63.4
 15-24
1 219
868
71.2
 25-44
5 704
3 974
69.7
 45-64
22 543
18 582
82.4
 65-74
27 979
25 066
89.6
 75 and over
119 247
110 730
92.9
Indigenous Status   
 Aboriginal and Torres Strait Islander
3 246
2 315
71.3
 Non-Indigenous
173 186
156 546
90.4
 Not stated
948
796
84.0
State of usual residence   
 NSW
59 887
54 077
90.3
 Vic.
43 130
38 915
90.2
 Qld
34 017
30 463
89.6
 SA
15 349
14 045
91.5
 WA
16 269
14 439
88.8
 Tas.
5 315
4 832
90.9
 NT
1 077
785
72.9
 ACT
2 294
2 066
90.1
Marital status   
 Never married
18 547
14 774
79.7
 Married
70 298
64 811
92.2
 Widow
64 004
59 249
92.6
 Divorced
18 268
15 807
86.5
 Separated
152
123
80.9
 Not applicable (<15 years)
6 111
4 893
80.1
Elapsed time between Census and death   
 Within 6 months of Census
80 234
71 238
88.8
 Beyond 6 months of Census
97 146
88 419
91.0


The linkage success varied by state of usual residence as reported on the death registration form. Rates were highest for South Australia (91.5%) and lowest for the Northern Territory (72.9%). All other states and territories had linkage rates between 88.8% and 90.9%. The low linkage rate for the Northern Territory reflects comparatively low linkage rates for both the Aboriginal and Torres Strait Islander and non-Indigenous populations. The linkage rate was similar for married and widowed persons (92.2 and 92.6% respectively). The linkage rate was lower for deaths which occurred within six months of the Census (88.8%) than those which occurred beyond six months after the Census (91.0%).

The linkage success also varied by Indigenous status recorded on the death registration form. People of non-Indigenous origin on the death registration form had a considerably higher linkage success (90.4%) compared with people of Aboriginal and Torres Strait Islander origin (71.3%). A more strict approach to implementing the 2016 linkage clerical review resulted in a lower, but more accurate linkage rate then in 2010-2012. For further information about the linkage methodology, see 'Information Paper: Linking Death registrations to the 2016 Census' (cat. no. 3302.0.55.004) to be released in December 2018.

Use of the CDE study to derive Aboriginal and Torres Strait Islander deaths identification rates

The CDE study allows a direct comparison of Indigenous status recorded on the death registration and the Census data for what is highly likely to be the same individual, and enables estimation of the undercoverage of Aboriginal and Torres Strait Islander deaths in the death registration system.

Table 3.3 presents the outcomes of the CDE study for Aboriginal and Torres Strait Islander deaths in Australia. It provides a cross-classification of the linked death registrations and Census records by the Indigenous status and age groups recorded in the respective records. Similar tables for other states and territory (without an age breakdown) where there are sufficient deaths available are in data cube 4: Summary of Linked Deaths by Indigenous Status, Deaths Registrations and Census Identification, Selected States and Territory and Australia - 2016-2017 (cat. no. 3302.0.55.003).

3.3 Summary of linked deaths by Indigenous status, Australia - 2016-2017

  DEATH REGISTRATION CLASSIFICATION 
  Aboriginal and Torres Strait IslanderNon-IndigenousNot statedTotal
Census classificationno.no.no.no.
0-14 years    
 Aboriginal and Torres Strait Islander
27
8
1
36
 Non-Indigenous
2
388
3
393
 Not stated
0
6
0
6
 Total
29
402
4
435
15-59 years    
 Aboriginal and Torres Strait Islander
774
228
6
1,008
 Non-Indigenous
82
14,511
139
14,732
 Not stated
19
288
2
309
 Total
875
15,027
147
16,049
60 years and over    
 Aboriginal and Torres Strait Islander
1,084
476
7
1,567
 Non-Indigenous
285
135,047
611
135,943
 Not stated
42
5,592
27
5,661
 Total
1,411
141,115
645
143,171
All ages    
 Aboriginal and Torres Strait Islander
1,885
712
14
2,611
 Non-Indigenous
369
149,946
753
151,068
 Not stated
61
5,886
29
5,976
 Total
2,315
156,544
796
159,655

The table highlights a number of features:

  • of the 2,611 linked records identified as Aboriginal and Torres Strait Islander on the Census file, only 1,885 (72%) were identified as Aboriginal and Torres Strait Islander in death registrations;
  • the 1,885 records identified as Aboriginal and Torres Strait Islander in both datasets represented 81% (that is 1,885 / 2,315 * 100) of linked deaths identified as Aboriginal and Torres Strait Islander in death registrations;
  • there is misidentification of Indigenous status between the Census and death registrations (for example, Aboriginal and Torres Strait Islander in death registrations but non-Indigenous in Census, and vice versa);
  • the overall Aboriginal and Torres Strait Islander deaths identification rate indicated by these statistics is 89% (that is, 2,315 / 2,611* 100).
     

The above suggests that while there appears to be misidentification of Indigenous status between the Census and death registrations, the overall identification rate in the death registrations collection is quite high at the national level (89%).

At the same time, it needs to be recognised that at the national level, about 29% of Aboriginal and Torres Strait Islander deaths as recorded on the death registration form could not be linked to a Census record. This would occur due to missing or inconsistent information in the fields being used for linking and also undercount of the Aboriginal and Torres Strait Islander population in the Census counts. Despite these issues, it is considered that the linked data provide reasonable estimates of the identification rate of Aboriginal and Torres Strait Islander deaths.

For the purpose of compiling Aboriginal and Torres Strait Islander life tables, the Aboriginal and Torres Strait Islander ERP used was derived from Census counts adjusted by results of the Post Enumeration Survey (PES). The PES provides an independent check on Census coverage and also identifies key demographic characteristics of the population that have been missed or overcounted in the Census. In compiling Aboriginal and Torres Strait Islander ERP, Indigenous status reported by the PES was considered more reliable than that recorded in the Census.

Therefore, to be consistent with Aboriginal and Torres Strait Islander ERP calculations, the number of deaths reported as Aboriginal and Torres Strait Islander in Census in the CDE linked data were adjusted to a PES basis. It should be noted that these adjustments were only in respect of misclassifications of Indigenous status in the linked file. No attempt was, or could be, made for undercount identified in the PES; this is reflected in the non-matched death registrations.

Thus, the Aboriginal and Torres Strait Islander deaths identification rate using the linked data was derived by:

  1.  calculating the propensities, from PES, of being Aboriginal and Torres Strait Islander in PES given Census Indigenous status (to align the Census Indigenous status with the PES Indigenous status);
  2. applying the propensities to counts from the CDE linked data to obtain the expected number of deaths in Census on a PES basis; and
  3. taking the ratio of the number of deaths reported as Aboriginal and Torres Strait Islander in death registrations to that reported in Census on a PES basis to calculate the Aboriginal and Torres Strait Islander deaths identification rate.

The following step by step example illustrates the calculation of the identification rate of Aboriginal and Torres Strait Islander deaths for Australia using the improved method that include age-specific identification rates when calculating the underidentification adjustment.

Step 1: Calculation of propensities from PES data given in table 3.4

The propensities are calculated for persons who matched to Census and responded as Aboriginal and Torres Strait Islander in the PES to the Census Indigenous status question. They were estimated by the three response classes for the Census Indigenous status question: Aboriginal and Torres Strait Islander, non-Indigenous and not stated.

3.4 Indigenous status as reported in 2016 Census and 2016 Post Enumeration Survey(a), Australia

  PES RESPONSE 
  Aboriginal and Torres Strait IslanderNon-IndigenousTotal
Census classificationno.no.no.
0-14 years   
 Aboriginal and Torres Strait Islander
1,713
105
1,818
 Non-Indigenous
90
17,203
17,293
 Not stated
10
166
176
 Total
1,813
17,474
19,287
15-59 years   
 Aboriginal and Torres Strait Islander
3,217
209
3,426
 Non-Indigenous
140
53,729
53,869
 Not stated
28
352
380
 Total
3,385
54,290
57,675
60 years and over   
 Aboriginal and Torres Strait Islander
386
36
422
 Non-Indigenous
40
19,166
19,206
 Not stated
3
230
233
 Total
429
19,432
19,861
All ages   
 Aboriginal and Torres Strait Islander
5,316
350
5,666
 Non-Indigenous
270
90,098
90,368
 Not stated
41
748
789
 Total
5,627
91,196
96,823
a. This tables uses unweighted data for illustrative purposes. Weighted PES data was used when determining the propensities for calculating life tables.
 

The following example will refer to data for the 0-14 years age group in table 3.4:

  • P(ATSI/ATSI) = propensity of being Aboriginal and Torres Strait Islander in PES given Census Indigenous status is 'Aboriginal and Torres Strait Islander' is 1,713 / 1,818 = 0.9422
  • P(ATSI/NI) = propensity of being Aboriginal and Torres Strait Islander in PES given Census Indigenous status is 'non-Indigenous' is 90 / 17,293 = 0.0052
  • P(ATSI/NS) = propensity of being Aboriginal and Torres Strait Islander in PES given Census Indigenous status is 'not stated' is 10 / 176 = 0.0568
     

The above propensities are based on the unweighted PES data. In calculating Aboriginal and Torres Strait Islander ERP, weighted PES information was used. Therefore, to be consistent with Aboriginal and Torres Strait Islander ERP calculations, the propensities were calculated using the weighted PES data. This gave, for 0-14 years age group, P(ATSI/ATSI) = 0.8999 P(ATSI/NI) = 0.0044 and P(ATSI/NS) = 0.0446

The Australia level propensities P(ATSI/NI) and P(ATSI/NS) calculated above are based on relatively small numbers of PES responses (90 and 10 respectively for the 0-14 years age group). These propensities calculated at the state/territory level, while not disaggregated by age, are still unreliable as they are based on considerably smaller numbers of PES responses. To overcome this problem, national level P(ATSI/NI) and P(ATSI/NS) are used for the states and territories (though without any disaggregation by age, as outlined under Calculation of adjustment factor for the states and territory).

Step 2: Estimation of expected number of deaths in Census in linked data given in table 3.3 using PES Aboriginal and Torres Strait Islander propensities

The expected number of deaths in the Census in CDE linked data file, for persons aged 0-14 years, using PES Aboriginal and Torres Strait Islander propensities is:

  • = 36 * P(ATSI/ATSI) + 393 * P(ATSI/NI) + 6 * P(ATSI/NS)
  • = 36 * 0.8999 + 393 * 0.0044 + 6 * 0.0446
  • = 34
     

where the numbers 36, 393 and 6 are Aboriginal and Torres Strait Islander, non-Indigenous and not stated deaths in Census for the 0-14 years age group (table 3.3).

Step 3: Calculation of identification rate of Aboriginal and Torres Strait Islander deaths, Australia

The estimate of the Aboriginal and Torres Strait Islander deaths identification rate is then calculated by taking the ratio of the number of deaths reported as Aboriginal and Torres Strait Islander in death registrations to the number of deaths expected to be recorded as Aboriginal and Torres Strait Islander in Census using the PES Aboriginal and Torres Strait Islander propensities:

= 29 / 34

= 0.84

where 29 is the Aboriginal and Torres Strait Islander deaths in death registrations for the 0-14 years age group (table 3.3).

Step 4: Calculation of adjustment factor, Australia

The adjustment factor is taken to be the reciprocal of the identification rate of Aboriginal and Torres Strait Islander deaths:

= 1 / 0.84

= 1.19

In the linked data, 29 records for the 0-14 years age group were reported as Aboriginal and Torres Strait Islander on the death registration form (table 3.3). Of deaths linked to the Census, 34 were recorded as Aboriginal and Torres Strait Islander, after adjustment for classifying Indigenous status in the way that PES does. This means that fewer deaths were identified as Aboriginal and Torres Strait Islander in death registrations than were expected in Census on a PES basis. Therefore, for the 0-14 age group, the number of Aboriginal and Torres Strait Islander deaths according to death registrations needed multiplying by an adjustment factor of 1 / 0.84 = 1.19 to be comparable to the Aboriginal and Torres Strait Islander deaths expected to be recorded as such in the Census on a PES basis.

Steps 1-4 were repeated to calculate identification rates for the 15-59 and 60+ age groups. Identification rates were 0.93 and 0.92 for the 15-59 and 60+ age groups respectively.

3.5 Aboriginal and Torres Strait Islander identification rates(a), headline Australia(b) - 2015-2017

 0-1415-5960+Total(c)
Identification Rate
0.84
0.93
0.92
0.92
Adjustment Factor(d)
1.19
1.07
1.09
1.08
a. Identification rate and adjustment factor are calculated using unrounded data.
b. These life expectancy estimates are calculated taking age-specific identification rates into account.
c. Total included here as a summary comparison measure, since the rates were applied at the age group level.
d. Calculated as the reciprocal of the identification rate.
 

Calculation of adjustment factor for the states and territory

The procedure described above was used to derive Aboriginal and Torres Strait Islander deaths identification rates at the Australia level only. Identification rates for states, territory, remoteness areas and Index of Relative Socio-Economic Disadvantage were calculated using a similar method but without using age-specific identification rates. This method is detailed fully in Chapter 3 of Experimental Life Tables for Aboriginal and Torres Strait Islander Australians 2005-2007 (cat. no. 3302.0.55.003).

Due to small numbers of Aboriginal and Torres Strait Islander deaths in Victoria, South Australia, Tasmania and the Australian Capital Territory, it was not feasible to derive separate reliable Aboriginal and Torres Strait Islander deaths identification rates for these jurisdictions. Therefore, a single Aboriginal and Torres Strait Islander deaths identification rate was derived by grouping these together.

There is considerable variation in the identification rates at the state/territory level (table 3.6). The estimate is less than 1.0 for New South Wales, Western Australia and Victoria/South Australia/Tasmania/Australian Capital Territory/OT combined, which indicates a level of under-identification of Aboriginal and Torres Strait Islander deaths in death registrations relative to the Census on a PES basis. In contrast, Queensland and the Northern Territory indicates a slight over-representation of Aboriginal and Torres Strait Islander deaths in death registrations relative to the Census for linked records; that is, persons who are identified as Aboriginal and Torres Strait Islander in the death registrations collection exceeded those who identified as Aboriginal and Torres Strait Islander in the Census on a PES basis. There is no clear reason as to why this might be the case, although there is evidence that some Aboriginal and Torres Strait Islander deaths have a state of usual residence on the death registration that is different to the Census.

3.6 Aboriginal and Torres Strait Islander identification rates, state/territory and Australia - 2015-2017

 Aboriginal and Torres Strait Islander deaths according to death registrationsExpected number of Aboriginal and Torres Strait Islander deaths(a)Identification rateAdjustment factor(b)
State/territoryno.no.no.no.
NSW
689
1 004
0.69
1.46
Qld
654
637
1.03
0.97
WA
353
376
0.94
1.06
NT
277
266
1.04
0.96
Vic./SA/Tas./ACT/OT combined
342
619
0.55
1.81
Aust.(c)(d)
2 315
2 902
0.80
1.25
a. In Census if weighted PES Aboriginal and Torres Strait Islander propensities are used.
b. Calculated as the reciprocal of the identification rate.
c. These life expectancy estimates are calculated without taking age-specific identification rates into account.
d. Includes all states and territories.
 

Aboriginal and Torres Strait Islander deaths identification rates for 2015-2017 are similar to those for 2010-2012, with the exception of Queensland for which the identification rate substantially increased to 1.03 in 2015-2017 from 0.80 in 2010-2012. This increase in the identification rate was due to an increase in the number of deaths of Aboriginal and Torres Strait Islander people following the introduction of Medical Certificate of Cause of Death (MCCD) in Queensland in 2015. For more information see Chapter 2: Data Quality Issues for deaths data.

Using MCCD information only, Queensland identified an extra 163 Aboriginal and Torres Strait Islander deaths: 30, 40 and 93 deaths in 2015, 2016 and 2017 respectively. Of these, only 84 deaths were in-scope for linkage and 70 deaths were successfully linked to a corresponding Census record. The exclusion of 70 linked deaths reduced the identification rate to 0.96 from 1.03.

To produce life tables for the period 2015-2017, three-year average deaths, rather than three-year total deaths were used. Therefore, inclusion of 54 (=163 divided by 3) of the 163 deaths identified using MCCD only reduced life expectancy, but this was compensated by adjusting down the registered deaths by the identification rate of 1.03. On balance, including the MCCD only deaths produced exactly the same life expectancy for Aboriginal and Torres Strait Islander males and only 0.1 year higher life expectancy for females compared with those produced by excluding them.

3.7 Aboriginal and Torres Strait Islander identification rates, Remoteness Areas - 2015-2017

 Aboriginal and Torres Strait Islander deaths according to death registrationsExpected number of Aboriginal and Torres Strait Islander deaths(a)(e)Identification rateAdjustment factor(b)
Remoteness Areano.no.no.no.
Major Cities
732
973
0.75
1.33
Inner and Outer Regional
1 002
1308
0.77
1.30
Remote and Very Remote
581
609
0.95
1.05
Aust.(c)(d)
2 315
2 902
0.80
1.25
a. In Census if weighted PES Aboriginal and Torres Strait Islander propensities are used.
b. Calculated as the reciprocal of the identification rate.
c. These life expectancy estimates are calculated without taking age-specific identification rates into account.
d. Includes all states and territories.
e. Includes records for which remoteness classification is missing.
 

There is quite considerable variation in the identification rates by remoteness (table 3.7). The estimates of 0.75 for Major Cities and 0.77 for Inner and Outer Regional areas combined indicates a high level of under-identification of Aboriginal and Torres Strait Islander deaths in death registrations. In contrast, the identification rate of 0.95 for Remote and Very Remote areas combined indicates a much lower level of under-identification.

3.8 Aboriginal and Torres Strait Islander identification rates, Index of Relative Socio-economic Disadvantage - 2015-2017

 Aboriginal and Torres Strait Islander deaths according to death registrationsExpected number of Aboriginal and Torres Strait Islander deaths(a)Identification rateAdjustment factor(b)
 no.no.no.no.
Most disadvantaged 20%
1074
1219
0.88
1.14
Second most disadvantaged 20%
579
719
0.80
1.24
Middle 20%
378
500
0.76
1.32
Least disadvantaged 40%
264
439
0.60
1.66
a. In Census if weighted PES Aboriginal and Torres Strait Islander propensities are used.
b. Calculated as the reciprocal of the identification rate.
 

Sensitivity analysis

The following table is used to illustrate the impact on life expectancy at birth when the identification rate is 5% higher or lower than those included in table 3.6. The variation is largest for the Northern Territory and Western Australia for both males and females. Life expectancy varies from 65.9 to 67.3 for males and 69.2 to 70.5 for females in the Northern Territory, and from 66.2 to 67.6 for males and 71.2 to 72.4 for females in Western Australia.

3.9 Aboriginal and Torres Strait Islander life expectancy, assumed identification rates - 2015-2017

State/territoryIf death identification rate was 5% lessEstimated death identification rateIf death identification rate was 5% more
MALES
NSW
70.2
70.9
71.5
Qld
71.4
72.0
72.6
WA
66.2
66.9
67.6
NT
65.9
66.6
67.3
Aust.(a)(b)
69.3
70.0
70.6
FEMALES
NSW
75.4
75.9
76.4
Qld
75.9
76.4
76.9
WA
71.2
71.8
72.4
NT
69.2
69.9
70.5
Aust.(a)(b)
73.9
74.4
75.0
a. These life expectancy estimates are calculated without taking age-specific identification rates into account.
b. Includes all states and territories.
 

Discussion

The use of the CDE Indigenous Mortality Study to assess the identification rate of Aboriginal and Torres Strait Islander deaths in death registration data has a number of benefits but at the same time it has limitations. First, the obvious and most substantial benefit is that it enables direct calculation of identification rates. That is, they are derived by directly comparing Indigenous status as reported according to death registrations and Census data for linked records, as opposed to indirect and modelled estimates.

Second, no assumptions were necessary to derive the identification rates from the CDE study, whereas a number of subjective judgements and assumptions were necessary to produce identification rates prior to the 2005-2007 period.

The limitations of the CDE Indigenous Mortality Study relate to three main factors. First, the derived Aboriginal and Torres Strait Islander deaths identification rates relate to a restricted time frame from 9 August 2016 to 28 September 2017. It is not possible to accurately judge the appropriateness or otherwise of the derived Aboriginal and Torres Strait Islander deaths identification rates for past or future periods.

Second, of the 3,246 Aboriginal and Torres Strait Islander death records eligible for linkage, 931 (28.7%) were not linked to a corresponding Census record.Of all the unlinked records, 23.3% were in New South Wales, 27.1% in Queensland, 19.2% in Western Australia and 17.2% in the Northern Territory. While not unexpected given the relatively high Census undercount for Aboriginal and Torres Strait Islander Australians, there may be features or characteristics of the unlinked records that are quite different to the linked records and therefore may introduce some bias to the results. Sensitivity analysis (see Appendix 1) indicates this is likely to be small.

It should be noted that all unlinked Aboriginal and Torres Strait Islander deaths are included in life tables calculations, but they are excluded from the calculation of identification rates and the resulting adjustment factor that are applied to the life tables. To produce life tables for Aboriginal and Torres Strait Islander Australians, information on the number of Aboriginal and Torres Strait Islander deaths and the Aboriginal and Torres Strait Islander population are required. Data quality issues are discussed in Chapter 2: Quality issues with Aboriginal and Torres Strait Islander deaths and population data.

The life tables in this release are based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census results. To account for underidentification of Aboriginal and Torres Strait Islander deaths in death registrations, the numbers of Aboriginal and Torres Strait Islander deaths were adjusted according to the adjustment factors derived from the Census Data Enhancement Aboriginal and Torres Strait Islander Mortality Study. This is described in Chapter 3: Data linkage to derive Aboriginal and Torres Strait Islander deaths identification rates. The adjusted numbers of Aboriginal and Torres Strait Islander deaths in 2015, 2016 and 2017 were divided by three to obtain the average annual number of Aboriginal and Torres Strait Islander deaths over the period 2015-2017, and in conjunction with 30 June 2016 Aboriginal and Torres Strait Islander population estimates (mid-point between the 2015-2017 reference period) were used to calculate age-specific death rates for the Aboriginal and Torres Strait Islander population.

Third, as stated above, the propensities of Aboriginal and Torres Strait Islander identification as reported in the 2016 Census and 2016 PES are calculated for persons who matched to Census and PES. While PES is a sample representing the whole population, the current methodology implicitly assumes that the propensities based on the Census-PES match will apply for the death registrations linked to the Census. Appendix 1: Confidence Intervals provides some indication of the sensitivity of the estimates of Aboriginal and Torres Strait Islander life expectancy at birth to assumptions made when calculating it.

A further assumption relates to the application of identification rates, which assumed uniformity by age and sex - except for the headline Australia estimate (which used three broad age groups).

In spite of these limitations, the CDE Indigenous Mortality Study clearly shows the need to adjust for underidentification in Aboriginal and Torres Strait Islander death registrations.

Life tables

4.1 Life tables for Aborignal and Torres Strait Islander Australians, headline Australia estimates(a) - 2015-2017(b)

 MALESFEMALES
 lx(c)qx(d)Lx(e)ex(f)lx(c)qx(d)Lx(e)ex(f)
Ageno.rateno.yearsno.rateno.years
0
100000
0.00731
99357
71.6
100000
0.00695
99388
75.6
1-4
99269
0.00127
396751
71.1
99305
0.00096
396979
75.2
5-9
99143
0.00116
495429
67.2
99210
0.00077
495858
71.2
10-14
99029
0.00089
494922
62.3
99133
0.00084
495458
66.3
15-19
98940
0.00370
493787
57.3
99050
0.00256
494616
61.3
20-24
98574
0.00699
491147
52.5
98796
0.00328
493172
56.5
25-29
97885
0.01021
486924
47.9
98472
0.00457
491237
51.7
30-34
96885
0.01411
481006
43.4
98022
0.00793
488168
46.9
35-39
95518
0.01806
473276
39.0
97245
0.01135
483464
42.2
40-44
93793
0.02826
462338
34.6
96141
0.01624
476801
37.7
45-49
91142
0.03967
446673
30.6
94579
0.02251
467574
33.3
50-54
87527
0.04822
427084
26.7
92450
0.03274
454685
29.0
55-59
83307
0.05790
404475
22.9
89424
0.04188
437755
24.9
60-64
78483
0.08963
374830
19.2
85679
0.06142
415237
20.9
65-69
71449
0.11272
337110
15.8
80416
0.09366
383253
17.1
70-74
63395
0.17386
289422
12.5
72885
0.13349
340101
13.6
75-79
52374
0.25206
228865
9.6
63156
0.21427
281947
10.3
80-84
39172
0.34057
162510
7.1
49623
0.30290
210539
7.4
85 years and over
25832
1.00000
113972
4.4
34592
1.00000
157014
4.5
a. These life expectancy estimates are calculated taking age-specific identification rates into account.
b. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
c. lx-number of persons surviving to exact age x.
d. qx-proportion of persons dying between exact age x and exact age x+n, where n is the width of the age interval.
e. Lx-number of person years lived within the age interval x to x+n.
f. ex-expectation of life at exact age x. Age x refers to the first age listed in the five year age group.
 

4.2 Life tables for Aboriginal and Torres Strait Islander Australians, Australia for comparison(a) - 2015-2017(b)

 MALESFEMALES
 lx(c)qx(d)Lx(e)ex(f)lx(c)qx(d)Lx(e)ex(f)
Ageno.rateno.yearsno.rateno.years
0
100000
0.00739
99350
70.0
100000
0.00699
99385
74.4
1-4
99261
0.00126
396721
69.5
99301
0.00091
396977
74.0
5-9
99136
0.00114
495398
65.6
99211
0.00078
495861
70.0
10-14
99023
0.00086
494903
60.6
99134
0.00071
495492
65.1
15-19
98938
0.00412
493670
55.7
99063
0.00289
494600
60.1
20-24
98530
0.00798
490685
50.9
98777
0.00370
492970
55.3
25-29
97744
0.01154
485900
46.3
98411
0.00502
490822
50.5
30-34
96616
0.01630
479144
41.8
97918
0.00873
487450
45.7
35-39
95041
0.02019
470409
37.5
97063
0.01277
482215
41.1
40-44
93122
0.03183
458201
33.2
95823
0.01820
474755
36.6
45-49
90158
0.04583
440460
29.2
94079
0.02458
464613
32.2
50-54
86026
0.05558
418175
25.5
91766
0.03688
450369
28.0
55-59
81244
0.06672
392670
21.8
88381
0.04728
431460
24.0
60-64
75824
0.09977
360205
18.2
84203
0.06726
406855
20.0
65-69
68258
0.12663
319683
14.9
78539
0.10622
371841
16.3
70-74
59615
0.19923
268381
11.7
70197
0.15314
324111
12.9
75-79
47738
0.28960
204125
9.0
59447
0.23795
261873
9.8
80-84
33913
0.38281
137107
6.7
45302
0.34112
187876
7.1
85 years and over
20930
1.00000
90435
4.3
29849
1.00000
133570
4.5
a. These life expectancy estimates are calculated without taking age-specific identification rates into account.
b. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
c. lx-number of persons surviving to exact age x.
d. qx-proportion of persons dying between exact age x and exact age x+n, where n is the width of the age interval.
e. Lx-number of person years lived within the age interval x to x+n.
f. ex-expectation of life at exact age x. Age x refers to the first age listed in the five year age group.
 

4.3 Life tables for Aboriginal and Torres Strait Islander Australians, New South Wales(a) - 2015-2017(b)

 MALESFEMALES
 lx(c)qx(d)Lx(e)ex(f)lx(c)qx(d)Lx(e)ex(f)
Ageno.rateno.yearsno.rateno.years
0
100000
0.00616
99458
70.9
100000
0.00525
99538
75.9
1-4
99384
0.00102
397273
70.3
99475
0.00064
397742
75.3
5-9
99282
0.00076
496223
66.4
99412
0.00095
496823
71.4
10-14
99207
0.00016
495995
61.4
99317
0.00010
496563
66.4
15-19
99191
0.00448
494844
56.5
99308
0.00180
496090
61.5
20-24
98747
0.00669
492081
51.7
99129
0.00326
494834
56.6
25-29
98086
0.01068
487811
47.0
98805
0.00473
492857
51.7
30-34
97039
0.01692
481087
42.5
98338
0.00783
489764
47.0
35-39
95396
0.01902
472445
38.2
97568
0.01028
485331
42.3
40-44
93582
0.02601
461825
33.9
96564
0.01418
479399
37.7
45-49
91148
0.04645
445156
29.7
95195
0.02065
471062
33.2
50-54
86914
0.05423
422787
26.1
93230
0.02953
459265
28.9
55-59
82201
0.05980
398715
22.4
90476
0.04316
442620
24.7
60-64
77285
0.09434
368198
18.7
86571
0.05621
420692
20.7
65-69
69994
0.12685
327773
15.4
81705
0.09453
389218
16.8
70-74
61115
0.18776
276888
12.2
73982
0.14549
342999
13.3
75-79
49640
0.25638
216384
9.5
63218
0.21070
282789
10.1
80-84
36913
0.36373
151001
6.9
49898
0.34042
207024
7.1
85 years and over
23487
1.00000
102657
4.4
32912
1.00000
148674
4.5
a. These life expectancy estimates are calculated without taking age-specific identification rates into account.
b. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
c. lx-number of persons surviving to exact age x.
d. qx-proportion of persons dying between exact age x and exact age x+n, where n is the width of the age interval.
e. Lx-number of person years lived within the age interval x to x+n.
f. ex-expectation of life at exact age x. Age x refers to the first age listed in the five year age group.
 

4.4 Life tables for Aboriginal and Torres Strait Islander Australians, Queensland(a) - 2015-2017(b)

 MalesFemales
 lx(c)qx(d)Lx(e)ex(f)lx(c)qx(d)Lx(e)ex(f)
Ageno.rateno.yearsno.rateno.years
0
100000
0.00675
99406
72.0
100000
0.00703
99381
76.4
1-4
99325
0.00106
397030
71.5
99297
0.00073
397009
76.0
5-9
99219
0.00128
495780
67.6
99224
0.00109
495851
72.0
10-14
99092
0.00076
495273
62.7
99116
0.00092
495354
67.1
15-19
99017
0.00347
494225
57.7
99025
0.00243
494523
62.2
20-24
98673
0.00709
491616
52.9
98784
0.00307
493163
57.3
25-29
97973
0.00815
487870
48.2
98481
0.00294
491681
52.5
30-34
97175
0.01229
482889
43.6
98191
0.00565
489570
47.6
35-39
95981
0.01424
476488
39.1
97637
0.00643
486615
42.9
40-44
94614
0.02565
467005
34.7
97009
0.01368
481730
38.1
45-49
92188
0.03369
453173
30.5
95683
0.02210
473125
33.6
50-54
89082
0.03955
436601
26.5
93567
0.02643
461654
29.3
55-59
85559
0.05412
416217
22.5
91094
0.03967
446438
25.1
60-64
80928
0.08930
386572
18.6
87481
0.06270
423691
21.0
65-69
73701
0.12418
345623
15.2
81996
0.08461
392634
17.2
70-74
64548
0.17763
294077
12.0
75058
0.12590
351665
13.6
75-79
53082
0.27416
229030
9.1
65608
0.21834
292227
10.2
80-84
38530
0.41205
152958
6.5
51283
0.31183
216435
7.3
85 years and over
22653
1.00000
98659
4.4
35291
1.00000
160493
4.5
a. These life expectancy estimates are calculated without taking age-specific identification rates into account.
b. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
c. lx-number of persons surviving to exact age x.
d. qx-proportion of persons dying between exact age x and exact age x+n, where n is the width of the age interval.
e. Lx-number of person years lived within the age interval x to x+n.
f. ex-expectation of life at exact age x. Age x refers to the first age listed in the five year age group.
 

4.5 Life tables for Aboriginal and Torres Strait Islander Australians, Western Australia(a) - 2015-2017(b)

 MALESFEMALES
 lx(c)qx(d)Lx(e)ex(f)lx(c)qx(d)Lx(e)ex(f)
Ageno.rateno.yearsno.rateno.years
0
100000
0.00917
99193
66.9
100000
0.00730
99357
71.8
1-4
99083
0.00151
395947
66.5
99270
0.00221
396492
71.3
5-9
98933
0.00155
494284
62.6
99050
0.00063
495095
67.5
10-14
98780
0.00198
493411
57.7
98988
0.00231
494368
62.5
15-19
98584
0.00565
491528
52.8
98759
0.00488
492591
57.6
20-24
98027
0.00958
487786
48.1
98277
0.00556
490019
52.9
25-29
97088
0.01725
481253
43.6
97730
0.00941
486352
48.2
30-34
95413
0.01875
472594
39.3
96811
0.01247
481034
43.6
35-39
93624
0.02712
461774
35.0
95603
0.02532
471962
39.2
40-44
91085
0.04430
445339
30.9
93182
0.02525
460027
35.1
45-49
87050
0.05762
422712
27.2
90829
0.02944
447459
30.9
50-54
82034
0.06891
396039
23.7
88155
0.04301
431295
26.8
55-59
76381
0.08485
365703
20.3
84363
0.05927
409316
22.9
60-64
69900
0.11605
329221
16.9
79363
0.08120
380707
19.2
65-69
61788
0.17737
281544
13.8
72919
0.11641
343375
15.7
70-74
50829
0.23086
224811
11.3
64430
0.17248
294371
12.4
75-79
39095
0.30095
166061
8.9
53318
0.26578
231162
9.5
80-84
27329
0.38544
110312
6.6
39147
0.35068
161414
7.0
85 years and over
16796
1.00000
70965
4.2
25419
1.00000
111974
4.4
a. These life expectancy estimates are calculated without taking age-specific identification rates into account.
b. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
c. lx-number of persons surviving to exact age x.
d. qx-proportion of persons dying between exact age x and exact age x+n, where n is the width of the age interval.
e. Lx-number of person years lived within the age interval x to x+n.
f. ex-expectation of life at exact age x. Age x refers to the first age listed in the five year age group.
 

4.6 Life tables for Aboriginal and Torres Strait Islander Australians, Northern Territory(a) - 2015-2017(b)

 MALESFEMALES
 lx(c)qx(d)Lx(e)ex(f)lx(c)qx(d)Lx(e)ex(f)
Ageno.rateno.yearsno.rateno.years
0
100000
0.01220
98926
66.6
100000
0.01374
98791
69.9
1-4
98780
0.00295
394349
66.4
98626
0.00183
394050
69.8
5-9
98488
0.00163
492038
62.6
98446
0.00010
492206
66.0
10-14
98327
0.00166
491226
57.7
98436
0.00184
491728
61.0
15-19
98163
0.00585
489381
52.8
98255
0.00393
490309
56.1
20-24
97589
0.00921
485697
48.1
97869
0.00434
488281
51.3
25-29
96690
0.01343
480203
43.6
97444
0.00837
485180
46.5
30-34
95392
0.01476
473439
39.1
96628
0.01554
479387
41.9
35-39
93984
0.02667
463653
34.7
95127
0.01709
471570
37.5
40-44
91477
0.03591
449174
30.5
93501
0.02823
460907
33.1
45-49
88192
0.04702
430594
26.6
90862
0.04341
444449
29.0
50-54
84045
0.07827
403780
22.8
86918
0.05851
421874
25.2
55-59
77467
0.09389
369149
19.5
81832
0.07751
393302
21.6
60-64
70193
0.13483
327306
16.3
75489
0.10062
358456
18.2
65-69
60729
0.16596
278449
13.4
67894
0.14529
314807
15.0
70-74
50651
0.25069
221509
10.6
58029
0.18070
263932
12.1
75-79
37953
0.34641
156897
8.3
47544
0.28912
203353
9.2
80-84
24806
0.42477
97687
6.3
33798
0.35715
138812
6.9
85 years and over
14269
1.00000
59279
4.2
21727
1.00000
94230
4.3
a. These life expectancy estimates are calculated without taking age-specific identification rates into account.
b. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
c. lx-number of persons surviving to exact age x.
d. qx-proportion of persons dying between exact age x and exact age x+n, where n is the width of the age interval.
e. Lx-number of person years lived within the age interval x to x+n.
f. ex-expectation of life at exact age x. Age x refers to the first age listed in the five year age group.
 

4.7 Life tables for Aboriginal and Torres Strait Islander Australians, Major Cities(a) –2015-2017(b)

 MALESFEMALES
 lx(c)qx(d)Lx(e)ex(f)lx(c)qx(d)Lx(e)ex(f)
Ageno.rateno.yearsno.rateno.years
0
100000
0.00753
99337
72.1
100000
0.00424
99627
76.5
1-4
99247
0.00086
396775
71.6
99576
0.00091
398064
75.8
5-9
99161
0.00089
495585
67.7
99485
0.00079
497227
71.9
10-14
99073
0.00067
495198
62.7
99406
0.00043
496922
66.9
15-19
99006
0.00260
494389
57.8
99363
0.00185
496355
62.0
20-24
98749
0.00654
492133
52.9
99179
0.00206
495384
57.1
25-29
98104
0.01042
487963
48.2
98974
0.00216
494339
52.2
30-34
97082
0.01313
482221
43.7
98761
0.00724
492019
47.3
35-39
95807
0.01817
474682
39.3
98046
0.01208
487270
42.6
40-44
94066
0.02434
464607
35.0
96862
0.01495
480687
38.1
45-49
91777
0.04159
449340
30.8
95413
0.02246
471710
33.7
50-54
87959
0.04677
429512
27.0
93271
0.03138
459035
29.4
55-59
83846
0.05873
406918
23.2
90344
0.03995
442694
25.2
60-64
78921
0.08601
377636
19.5
86734
0.05714
421281
21.2
65-69
72133
0.10792
341204
16.1
81778
0.08358
391803
17.3
70-74
64349
0.17238
294012
12.7
74943
0.14408
347720
13.7
75-79
53256
0.23502
234991
9.8
64145
0.20481
287880
10.6
80-84
40740
0.33547
169532
7.1
51007
0.27452
220029
7.6
85 years and over
27073
1.00000
120001
4.4
37004
1.00000
169046
4.6
a. These life expectancy estimates are calculated without taking age-specific identification rates into account.
b. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
c. lx-number of persons surviving to exact age x.
d. qx-proportion of persons dying between exact age x and exact age x+n, where n is the width of the age interval.
e. Lx-number of person years lived within the age interval x to x+n.
f. ex-expectation of life at exact age x. Age x refers to the first age listed in the five year age group.
 

4.8 Life tables for Aboriginal and Torres Strait Islander Australians, Inner and Outer Regional combined(a) –2015-2017(b)

 MALESFEMALES
 lx(c)qx(d)Lx(e)ex(f)lx(c)qx(d)Lx(e)ex(f)
Ageno.rateno.yearsno.rateno.years
0
100000
0.00628
99448
70.0
100000
0.00801
99295
74.8
1-4
99372
0.00118
397184
69.4
99199
0.00052
396678
74.4
5-9
99255
0.00137
495935
65.5
99147
0.00041
495634
70.5
10-14
99119
0.00075
495409
60.6
99107
0.00066
495370
65.5
15-19
99044
0.00483
494026
55.6
99041
0.00258
494569
60.5
20-24
98566
0.00761
490955
50.9
98786
0.00457
492802
55.7
25-29
97816
0.01156
486254
46.3
98334
0.00502
490438
50.9
30-34
96685
0.01859
478933
41.8
97841
0.00898
487007
46.2
35-39
94888
0.01817
470131
37.5
96962
0.00974
482450
41.6
40-44
93164
0.03355
458006
33.2
96018
0.01544
476383
37.0
45-49
90038
0.04313
440482
29.2
94535
0.02240
467384
32.5
50-54
86155
0.05218
419534
25.4
92418
0.03470
454074
28.2
55-59
81659
0.06295
395445
21.7
89212
0.04511
435998
24.1
60-64
76519
0.10321
362851
18.0
85188
0.06773
411515
20.1
65-69
68621
0.13786
319456
14.8
79418
0.10540
376163
16.4
70-74
59161
0.18350
268666
11.8
71047
0.15647
327445
13.0
75-79
48305
0.29681
205682
8.8
59931
0.21066
268091
10.0
80-84
33968
0.41161
134884
6.5
47306
0.35583
194446
7.0
85 years and over
19986
1.00000
85955
4.3
30473
1.00000
136637
4.5
a. These life expectancy estimates are calculated without taking age-specific identification rates into account.
b. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
c. lx-number of persons surviving to exact age x.
d. qx-proportion of persons dying between exact age x and exact age x+n, where n is the width of the age interval.
e. Lx-number of person years lived within the age interval x to x+n.
f. ex-expectation of life at exact age x. Age x refers to the first age listed in the five year age group.
 

4.9 Life tables for Aboriginal and Torres Strait Islander Australians, Remote and Very Remote combined(a) –2015-2017(b)

 MALESFEMALES
 lx(c)qx(d)Lx(e)ex(f)lx(c)qx(d)Lx(e)ex(f)
Ageno.rateno.yearsno.rateno.years
0
100000
0.01158
98981
65.9
100000
0.01249
98901
69.6
1-4
98842
0.00255
394706
65.7
98751
0.00225
394430
69.5
5-9
98590
0.00150
492581
61.8
98529
0.00178
492206
65.7
10-14
98442
0.00184
491758
56.9
98353
0.00220
491226
60.8
15-19
98261
0.00663
489676
52.0
98137
0.00624
489154
55.9
20-24
97609
0.01251
484995
47.3
97524
0.00577
486216
51.3
25-29
96389
0.01481
478374
42.9
96962
0.01063
482234
46.5
30-34
94961
0.01762
470621
38.5
95931
0.01229
476708
42.0
35-39
93288
0.02897
459682
34.2
94752
0.01996
469032
37.5
40-44
90585
0.04351
443074
30.1
92861
0.03066
457188
33.2
45-49
86644
0.05728
420815
26.4
90014
0.03777
441572
29.2
50-54
81682
0.07551
392989
22.8
86615
0.05273
421654
25.2
55-59
75514
0.08803
360951
19.5
82047
0.06715
396462
21.5
60-64
68866
0.12351
323067
16.1
76538
0.09366
364766
17.9
65-69
60361
0.17242
275785
13.0
69369
0.14800
321179
14.5
70-74
49953
0.25934
217379
10.2
59102
0.19699
266406
11.5
75-79
36998
0.36276
151438
7.9
47460
0.30567
201032
8.7
80-84
23577
0.46254
90621
6.0
32953
0.41072
130928
6.5
85 years and over
12672
1.00000
51990
4.1
19419
1.00000
83271
4.3
a. These life expectancy estimates are calculated without taking age-specific identification rates into account.
b. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
c. lx-number of persons surviving to exact age x.
d. qx-proportion of persons dying between exact age x and exact age x+n, where n is the width of the age interval.
e. Lx-number of person years lived within the age interval x to x+n.
f. ex-expectation of life at exact age x. Age x refers to the first age listed in the five year age group.
 

4.10 Life tables for Aboriginal and Torres Strait Islander Australians, by Index of Relative Socio-economic Disadvantage(a), most disadvantaged 20% –2015-2017(b)

 MALESFEMALES
 lx(c)qx(d)Lx(e)ex(f)lx(c)qx(d)Lx(e)ex(f)
Ageno.rateno.yearsno.rateno.years
0
100000
0.00865
99239
68.2
100000
0.00841
99260
72.8
1-4
99135
0.00150
396155
67.8
99159
0.00138
396285
72.4
5-9
98986
0.00142
494580
63.9
99022
0.00140
494765
68.5
10-14
98846
0.00106
493967
59.0
98883
0.00168
494002
63.6
15-19
98741
0.00618
492178
54.0
98717
0.00387
492633
58.7
20-24
98130
0.00853
488559
49.3
98336
0.00380
490746
53.9
25-29
97293
0.01343
483201
44.7
97962
0.00718
488053
49.1
30-34
95987
0.01740
475758
40.3
97259
0.01006
483847
44.4
35-39
94316
0.02411
465898
36.0
96280
0.01511
477763
39.9
40-44
92043
0.03943
451140
31.8
94825
0.02408
468416
35.4
45-49
88413
0.05567
429762
28.0
92541
0.03208
455285
31.2
50-54
83492
0.06629
403621
24.5
89573
0.04327
438174
27.2
55-59
77957
0.08201
373801
21.1
85697
0.05675
416326
23.3
60-64
71563
0.11148
337873
17.7
80834
0.07494
389023
19.6
65-69
63586
0.13975
295714
14.7
74776
0.11341
352677
15.9
70-74
54700
0.20616
245307
11.6
66295
0.16286
304485
12.7
75-79
43423
0.28336
186353
9.0
55499
0.25238
242477
9.6
80-84
31118
0.39778
124646
6.6
41492
0.34474
171700
7.0
85 years and over
18740
1.00000
80072
4.3
27188
1.00000
120562
4.4
a. These life expectancy estimates are calculated without taking age-specific identification rates into account.
b. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
c. lx-number of persons surviving to exact age x.
d. qx-proportion of persons dying between exact age x and exact age x+n, where n is the width of the age interval.
e. Lx-number of person years lived within the age interval x to x+n.
f. ex-expectation of life at exact age x. Age x refers to the first age listed in the five year age group.
 

4.11 Life tables for Aboriginal and Torres Strait Islander Australians, by Index of Relative Socio-economic Disadvantage(a), second most disadvantaged 20% –2015-2017(b)

 MALESFEMALES
 lx(c)qx(d)Lx(e)ex(f)lx(c)qx(d)Lx(e)ex(f)
Ageno.rateno.yearsno.rateno.years
0
100000
0.00695
99388
70.3
100000
0.00634
99442
75.5
1-4
99305
0.00068
397056
69.8
99366
0.00054
397334
75.0
5-9
99238
0.00086
495975
65.9
99312
0.00018
496515
71.1
10-14
99153
0.00109
495494
60.9
99294
0.00060
496322
66.1
15-19
99045
0.00238
494634
56.0
99235
0.00247
495560
61.1
20-24
98809
0.00810
492043
51.1
98989
0.00412
493927
56.3
25-29
98009
0.01350
486736
46.5
98582
0.00488
491706
51.5
30-34
96686
0.02040
478499
42.1
98101
0.00925
488236
46.7
35-39
94714
0.01941
468972
37.9
97194
0.00990
483563
42.1
40-44
92875
0.03424
456425
33.7
96232
0.01321
477981
37.5
45-49
89695
0.04078
439331
29.8
94961
0.01821
470480
33.0
50-54
86037
0.05462
418437
25.9
93231
0.03192
458717
28.6
55-59
81338
0.06034
394418
22.3
90255
0.04133
441951
24.4
60-64
76430
0.09242
364489
18.5
86525
0.06671
418195
20.4
65-69
69366
0.12941
324387
15.2
80753
0.10566
382436
16.6
70-74
60389
0.18671
273756
12.1
72221
0.14845
334302
13.3
75-79
49114
0.26976
212446
9.2
61500
0.20724
275636
10.2
80-84
35865
0.38086
145175
6.7
48755
0.32777
203822
7.2
85 years and over
22205
1.00000
96515
4.3
32774
1.00000
147993
4.5
a. These life expectancy estimates are calculated without taking age-specific identification rates into account.
b. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
c. lx-number of persons surviving to exact age x.
d. qx-proportion of persons dying between exact age x and exact age x+n, where n is the width of the age interval.
e. Lx-number of person years lived within the age interval x to x+n.
f. ex-expectation of life at exact age x. Age x refers to the first age listed in the five year age group. 
 

4.12 Life tables for Aboriginal and Torres Strait Islander Australians, by Index of Relative Socio-economic Disadvantage(a), middle 20% –2015-2017(b)

 MALESFEMALES
 lx(c)qx(d)Lx(e)ex(f)lx(c)qx(d)Lx(e)ex(f)
Ageno.rateno.yearsno.rateno.years
0
100000
0.00776
99317
69.9
100000
0.00754
99337
74.3
1-4
99224
0.00196
396382
69.4
99246
0.00105
396721
73.9
5-9
99029
0.00100
494900
65.6
99142
0.00026
495647
69.9
10-14
98930
0.00063
494497
60.6
99117
0.00055
495446
65.0
15-19
98868
0.00404
493342
55.7
99062
0.00238
494718
60.0
20-24
98469
0.00888
490157
50.9
98826
0.00556
492753
55.1
25-29
97594
0.01170
485117
46.3
98276
0.00322
490587
50.4
30-34
96453
0.01478
478698
41.8
97959
0.00809
487813
45.6
35-39
95027
0.02482
469235
37.4
97166
0.01711
481676
40.9
40-44
92668
0.02515
457511
33.3
95504
0.01787
473253
36.6
45-49
90337
0.04542
441425
29.1
93797
0.02579
462938
32.2
50-54
86233
0.05261
419824
25.4
91378
0.04027
447690
28.0
55-59
81696
0.07558
393045
21.6
87698
0.04803
427961
24.1
60-64
75522
0.10321
358121
18.2
83486
0.07066
402683
20.2
65-69
67727
0.13679
315473
15.0
77587
0.10935
366726
16.5
70-74
58462
0.19021
264511
12.0
69103
0.15128
319381
13.2
75-79
47342
0.27580
204069
9.2
58649
0.22003
260983
10.2
80-84
34285
0.37297
139458
6.8
45744
0.31178
193066
7.3
85 years and over
21498
1.00000
93137
4.3
31482
1.00000
141609
4.5
a. These life expectancy estimates are calculated without taking age-specific identification rates into account.
b. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
c. lx-number of persons surviving to exact age x.
d. qx-proportion of persons dying between exact age x and exact age x+n, where n is the width of the age interval.
e. Lx-number of person years lived within the age interval x to x+n.
f. ex-expectation of life at exact age x. Age x refers to the first age listed in the five year age group. 
 

4.13 Life tables for Aboriginal and Torres Strait Islander Australians, by Index of Relative Socio-economic Disadvantage(a), least disadvantaged 40% –2015-2017(b)

 MALESFEMALES
 lx(c)qx(d)Lx(e)ex(f)lx(c)qx(d)Lx(e)ex(f)
Ageno.rateno.yearsno.rateno.years
0
100000
0.00584
99486
72.4
100000
0.00557
99510
76.6
1-4
99416
0.00122
397347
71.8
99443
0.00043
397672
76.0
5-9
99295
0.00160
496077
67.9
99400
0.00080
496802
72.1
10-14
99136
0.00082
495476
63.0
99320
0.00041
496500
67.1
15-19
99055
0.00240
494679
58.0
99280
0.00209
495880
62.1
20-24
98817
0.00716
492315
53.2
99072
0.00136
495026
57.3
25-29
98109
0.00682
488874
48.5
98938
0.00263
494040
52.3
30-34
97440
0.01111
484496
43.9
98678
0.00805
491404
47.5
35-39
96358
0.01207
478883
39.3
97884
0.00781
487506
42.8
40-44
95195
0.02419
470218
34.8
97119
0.01302
482432
38.1
45-49
92892
0.03041
457401
30.6
95854
0.02287
473789
33.6
50-54
90068
0.04073
441169
26.4
93662
0.02989
461310
29.3
55-59
86399
0.04753
421731
22.5
90862
0.03441
446496
25.2
60-64
82293
0.07984
395040
18.5
87736
0.05396
426844
21.0
65-69
75723
0.11594
356665
14.8
83002
0.07247
399971
17.0
70-74
66943
0.18802
303250
11.5
76987
0.11227
363326
13.2
75-79
54357
0.29229
232063
8.5
68344
0.23368
301793
9.5
80-84
38469
0.48092
146093
6.0
52373
0.40473
208874
6.7
85 years and over
19969
1.00000
85872
4.3
31176
1.00000
140101
4.5
a. These life expectancy estimates are calculated without taking age-specific identification rates into account.
b. Based on the average number of Aboriginal and Torres Strait Islander deaths registered in 2015-2017 adjusted for under/over identification of Indigenous Status in registrations, and final Aboriginal and Torres Strait Islander population estimates for 30 June 2016 based on the 2016 Census.
c. lx-number of persons surviving to exact age x.
d. qx-proportion of persons dying between exact age x and exact age x+n, where n is the width of the age interval.
e. Lx-number of person years lived within the age interval x to x+n.
f. ex-expectation of life at exact age x. Age x refers to the first age listed in the five year age group.

Frequently asked questions

On 29 November, 2018 the ABS released the latest official estimates of life expectancy for Aboriginal and Torres Strait Islander peoples. These are the sixth set of life expectancy estimates released by the ABS since the first set was released in 1997.

The latest estimates show that in 2015-2017, life expectancy at birth for Aboriginal and Torres Strait Islander men was 71.6 years and 75.6 years for women. This suggests that Aboriginal and Torres Strait Islander men, on average, live 8.6 years less than non-Indigenous men, while Aboriginal and Torres Strait Islander women, on average, live 7.8 years less than non-Indigenous women. This gap has reduced over the last five years by 2.0 years for men and 1.7 years for women. This means, 71.6 is the average number of years that a group of newborn male babies would be expected to live if current death rates remain unchanged. For newborn Aboriginal and Torres Strait Islander female babies, the average number is 75.6 years.

What is life expectancy?

Life expectancy summarises the mortality experience of a population by measuring how long, on average, a group of people born in the same year would be expected to live, if current death rates at each age remained the same. Life expectancy can be calculated for any age using life tables (a table which shows the probability of dying at each age), though life expectancy at birth is what most people focus on. Life expectancy at birth is the average number of years that a group of newborn babies would be expected to live if current death rates remain unchanged. Since death rates in the population will change during a person’s lifetime and a person may die at an earlier or older age, life expectancy is only a summary indicator for a population, rather than an exact measure of how long individuals will actually live.

By the time a child reaches their first birthday, their chances of living longer increase (since they have survived their first year). By the time they reach late adulthood, their chances of surviving to a very old age are quite good. For example, although the average life expectancy for Aboriginal and Torres Strait Islander male is 71.6 years, a five year old is expected to live another 67.2 years, making their life expectancy 72.2 years. If an Aboriginal and Torres Strait Islander man reaches age 65, they will have an expected average of 15.8 additional years left to live, making their life expectancy 80.8 years, 9.2 years longer than the average life expectancy at birth.

Does that mean that most people will only live to 71.6 years and 75.6 years?

The latest estimates show that Aboriginal and Torres Strait Islander men born in 2015-2017 would live to an average of 71.6 years, while women would live to an average of 75.6 years if current mortality rates continued. However, this does not mean that all or most Aboriginal and Torres Strait Islander people born during 2015-2017 will die at or around these ages. These are average values, so some people die before reaching the average life expectancy at birth (including in their first year), while others will live well beyond that age.

What is life expectancy used for?

Life expectancy is widely used as a key measure of the health of a population. Since life expectancy is expressed in years of life, it is often seen as an indicator that is more easily interpreted than other measures of mortality (e.g. standardised death rates, preventable death rates, etc). Life expectancy is also not affected by different population age structures, so can be compared across subpopulations, jurisdictions and over time. However, since it’s a summary measure, changes in life expectancy are often much smaller than the changes in other measures. For instance, life expectancy at birth for the population of Australia changed by around 0.3 years of life per year, from 1890 to 2015, despite major changes in infant and child mortality and other mortality trends.

Quantity of life versus quality of life

While life expectancy at birth measures how long, on average, a group of people born in the same year can expect to live, it does not take account of how healthy they are expected to be throughout their life. Health adjusted life expectancy estimates are not regularly published, with the most recent data published by the Australian Institute of Health and Welfare in: ‘Australian Burden of Disease Study: impact and causes of illness and death in Aboriginal and Torres Strait Islander people 2011’.

How does the ABS calculate life expectancy?

Life expectancy is calculated using life tables, which bring together deaths data and population estimates. By temporarily linking death registration records and Census records, the ABS is able to confirm that there are a number of deaths of Aboriginal and Torres Strait Islander people which are not identified as such on their death registration. From this the ABS is able to estimate how many deaths there would have been in the Aboriginal and Torres Strait Islander population, had all of the people who died been identified as they were in the Census. This method, known as the ‘direct method’, was first used by the ABS for Aboriginal and Torres Strait Islander life expectancy for 2005-2007. The estimates produced by this method are considered to be more accurate than those from the previous method (the ‘indirect method’, which required the ABS to make a range of assumptions in the calculation).

For the 2015-2017 estimates the ABS again used the ‘direct method’.

For further information see Life Tables for Aboriginal and Torres Strait Islander Australians, 2015—2017 (cat. no. 3302.0.55.003).

Data downloads

Table 1: Life tables for Aboriginal and Torres Strait Islander Australians, selected states and territory and Australia - 2015-2017

Table 2: Life tables for Aboriginal and Torres Strait Islander Australians, Remoteness Areas, Australia - 2015-2017

Table 3: Life tables for Aboriginal and Torres Strait Islander Australians, Index of Relative Socio-economic Disadvantage, Australia - 2015-2017

Table 4: Summary of linked deaths by Indigenous status, deaths registrations and Census identification, selected states and territory and Australia - 2016-2017

Table 5: Summary of linked deaths by Indigenous status, deaths registrations and Census identification, Remoteness Areas, Australia - 2016-2017

Table 6: Summary of linked deaths by Indigenous status, deaths registrations and Census identification, Index of Relative Socio-economic Disadvantage, Australia - 2016-2017

Table 7: Difference in Indigenous classification between Census and PES identification, unweighted and weighted data, selected states and territory and Australia - 2016

Table 8: Difference in Indigenous classification between Census and PES identification, unweighted and weighted data, Remoteness Areas, Australia - 2016

Table 9: Difference in Indigenous classification between Census and PES identification, unweighted and weighted data, Index of Relative Socio-economic Disadvantage, Australia - 2016

History of changes

Show all

25/03/2019 - This issue contains a revised description of the differences in ABS and AIHW methodologies used to produce Aboriginal and Torres Strait Islander life expectancy.

22/01/2019 - This issue contains additional confidence intervals and death identification rates for Aboriginal and Torres Strait Islander life expectancy by Index of Relative Socio-Economic Disadvantage.

Acknowledgements

We thank Australian Aboriginal and Torres Strait Islander peoples for their cooperation and assistance in the collection of data, without whom this analysis would not have been possible.

The ABS would like to recognise the valuable contribution made by key experts to the methods used by the ABS. In particular, the Aboriginal and Torres Strait Islander Demographic Statistics Expert Advisory Group has provided invaluable advice to the ABS in the lead-up to producing the 2015-2017 estimates.

Previous catalogue number

This release previously used catalogue number 3302.0.55.003.