Latest release

# Estimates and Projections, Aboriginal and Torres Strait Islander Australians methodology

Reference period
2006 - 2031
Released
11/07/2019
Next release Unknown
First release

## Explanatory notes

### Introduction

1 This release contains annual estimates and projections of the Aboriginal and Torres Strait Islander population of Australia from 30 June 2001 to 30 June 2016 and 30 June 2017 to 30 June 2031 respectively, based on results of the 2016 Census of Population and Housing.

2 These estimates and projections supersede the 2011-based series published in Estimates and Projections, Aboriginal and Torres Strait Islander Australians, 2001 to 2026 (cat. no. 3238.0) in April 2014.

### Data quality

3 The significant volatility in the Aboriginal and Torres Strait Islander Census counts and the quality of data on births, deaths and migration of Aboriginal and Torres Strait Islander persons do not support the use of the standard approach to population estimation (observed numbers of births, deaths and migration during a specified period are added to the population at the start of the period to obtain an estimate of the population at the end of the period).

4 Data quality issues relating to Aboriginal and Torres Strait Islander population estimates for 30 June 2016 derived from the 2016 Census of Population and Housing, on which the estimates and projections in this release are based, are discussed in more detail in paragraphs 9 to 22 of the Explanatory Notes of Estimates of Aboriginal and Torres Strait Islander Australians, June 2016 (cat. no. 3238.0.55.001) and the associated Technical Note: Estimated Aboriginal and Torres Strait Islander Australian Resident Population - Method of Calculation.

5 For a discussion of the measurement of deaths of Aboriginal and Torres Strait Islander persons, see the section 'Quality issues with Aboriginal and Torres Strait Islander deaths and population data' in Life Tables for Aboriginal and Torres Strait Islander Australians (cat. no. 3302.0.55.003).

### Indigenous status

6 The Aboriginal and Torres Strait Islander population comprises people who are of Aboriginal origin, Torres Strait Islander origin or both Aboriginal and Torres Strait Islander origin.

The Commonwealth definition of an Aboriginal or Torres Strait Islander person is:

• of Aboriginal and/or Torres Strait Islander descent
• who identifies as being of Aboriginal and/or Torres Strait Islander origin, and
• who is accepted as such by the community with which the person associates.

7 The 2016 Census of Population and Housing (Household Form) asked the following question of each person:

### 1. Diagram: Indigenous status question on 2016 Census form.

The question: Is the person of Aboriginal and Torres Strait Islander origin?

No
Yes, Aboriginal
Yes, Torres Strait Islander

Persons of both Aboriginal and Torres Strait Islander origin can mark both 'Yes' boxes.

The question is applicable to all persons.

The Indigenous status of a person is determined by their response to this question.

### Australian statistical areas

8 This release contains data presented according to a number of geographic classifications: the Main Structure of the Australian Statistical Geography Standard (ASGS), the Indigenous Structure, and Remoteness Areas (RAs).

9 For further information see:

### Age groups

10 Estimates and projections in this release are presented by five-year age groups, with upper age groups as follows:

• Australia, states and territories - 85 years and over (65 years and over for Tasmania and the Australian Capital Territory)
• Indigenous Regions - 65 years and over
• Remoteness Areas - 75 years and over

11 Estimates and projections in this release are also presented by single year of age, with upper age groups as follows:

• Australia, states and territories - 65 years and over
• Remoteness Areas - 65 years and over

12 It is important to recognise the inherent uncertainties in these data. Aboriginal and Torres Strait Islander population estimates for 30 June 2016, on which the estimates and projections in this release are based, may be subject to errors that cannot be comprehensively adjusted for in the population estimates compilation process. This is due to the inability of the Post Enumeration Survey to adjust for net undercount by Indigenous status by single year of age and sex. Features present in single year of age Census counts may be likely to appear in population estimates for 2016, even after adjustment for net undercount and other factors have been applied, and therefore may appear in single year of age estimates for earlier years as well as projections.

13 An age heaping adjustment was applied to the population of the Northern Territory, as part of compiling the final 30 June 2016 ERP based on the 2016 Census. This information was released in Estimates of Aboriginal and Torres Strait Islander Australians, June 2016 (cat. no. 3238.0.55.001) and has been used as the base population for the estimates and projections in this release.

14 In addition, the use of assumptions on future levels of fertility, mortality and migration to obtain population projections adds a further level of uncertainty, the extent of which cannot be measured.

### Methods

15 There are many techniques which may be used to produce population projections, such as simple extrapolations, probabilistic methods, broad economic, social and time-series analysis, and detailed component methods.

16 As mentioned above (see paragraphs 3-5), data quality issues relating to Census counts, births, deaths and migration of Aboriginal and Torres Strait Islander persons do not support the standard approach to population estimation. An alternative method is therefore required to enable the construction of a time series of the size and structure of the Aboriginal and Torres Strait Islander population.

17 Estimates of the Aboriginal and Torres Strait Islander population are available for 30 June of the latest Census year (currently, 30 June 2016). Based on these, estimates (for previous years) and projections (for future years) can be derived using assumptions about past and future components of population change.

18 Due to volatility in Aboriginal and Torres Strait Islander Census counts, estimates for previous years derived from the 30 June 2016 data provide a consistent time series compared to Census year estimates derived from previous censuses. The estimates and projections in this release therefore supersede previously published ABS estimates and projections of the Aboriginal and Torres Strait Islander population. See paragraphs 25-27 for a comparison of population estimates based on the 2011, 2006, and 2001 censuses.

### Cohort-component method

19 The ABS uses the cohort-component method, which begins with a base population for each sex by single year of age, and advances it year by year by applying assumptions regarding future fertility, mortality and migration. This procedure is repeated for each year in the projection period. Projections for each geographic region (for example, Remoteness Areas) by sex and single years of age are adjusted to sum to state or territory projections which are in turn adjusted to sum to Australia-level projections.

20 A similar technique can also be used to estimate past populations, by 'reverse-surviving' a population using mortality rates derived from life tables.

### Estimates

21 A single series of population estimates for the period 2001 to 2015 was calculated by reverse-surviving the 30 June 2016 estimated Aboriginal and Torres Strait Islander resident population using assumed life tables based on those calculated for the period 2015-2017. Zero net overseas migration was assumed for the period 2001 to 2016 and interstate migration levels were based on those measured in the corresponding intercensal period (i.e. 2001-2006, 2006-2011 and 2011-2016).

### Method used to derive estimates

22 Using 30 June 2016 Aboriginal and Torres Strait Islander resident population estimates as the base population, estimates were survived back one year at a time to 30 June 2001. For example, the number of 19-year old males in 2015 was obtained by applying survivorship ratios from life tables to the number of 20-year old males in 2016. This calculation is performed for all ages and both sexes to obtain the complete 2015 population, and repeated to obtain estimates for each year back to 2001.

23 Net interstate migration assumptions have been calculated directly from the net migration measured in the corresponding Census periods. As Census data indicates that the level of net overseas migration of Aboriginal and Torres Strait Islander persons is negligible, zero net overseas migration has been assumed.

24 For the estimates presented in this release, it was assumed that Aboriginal and Torres Strait Islander life expectancy at birth at the Australia level increased by 0.20 years per year for males and 0.15 years per year for females for the period 30 June 2001 to 30 June 2006 and then increased by 0.30 years per year for males and 0.20 years per year for females for the 2006-2011 period. For 2011- 2016, life expectancy at birth increased by 0.40 years per year for males and 0.25 years per year for females. Whether Aboriginal and Torres Strait Islander life expectancy at birth has changed at a faster or slower rate is unknown.

### Comparison to previously published estimates

25 The estimate for 30 June 2011 based on the 2011 Census was 669,900 Aboriginal and Torres Strait Islander persons. The estimate for 2011 presented in this release, based on the 2016 Census, is 720,100 persons (7.5% more than the previously published 2011 estimate).

26 The estimate for 30 June 2006 based on the 2006 Census was 517,000 Aboriginal and Torres Strait Islander persons. The estimate for 2006 presented in this release, based on the 2016 Census, is 640,000 persons (23.8% more than the previously published 2006 estimate).

27 The total Aboriginal and Torres Strait Islander population of Australia at 30 June 2001, based on the 2001 Census, was 458,500 persons. The estimate for 2001 presented in this release, based on the 2016 Census, is 565,200 persons ( 23.3% more than the previously published 2001 estimate).

### Projections

28 The ABS publishes Aboriginal and Torres Strait Islander population projections once every intercensal period. The projections are not intended as predictions or forecasts, but are illustrations of growth and change in the structure of the Aboriginal and Torres Strait Islander population that would occur if assumptions made about future demographic trends were to prevail over the projection period.

### Assumptions

29 Assumptions have been formulated on the basis of past demographic trends, in conjunction with consultation with various experts and government department representatives at the national and state/territory level.

30 The assumptions do not attempt to allow for non-demographic factors (such as major government policy decisions, economic factors, natural disasters, epidemics or significant health treatment improvements) which may affect future demographic behaviour or outcomes. There is no certainty that any of the assumptions will or will not be realised. Detailed information on the assumptions is described on the page: Assumptions.

31 Projections incorporating alternative levels and combinations of assumptions have been produced in recognition of this uncertainty and to provide a range of possible options to users (see the page: Sensitivity to Projection Assumptions for more information).

### Method used to derive projections

32 Using 30 June 2016 Aboriginal and Torres Strait Islander resident population estimates as the base population, the estimates were projected forward one year at a time to 30 June 2031. For example:

• the number of 21 year-old males in 2017 was obtained by applying survivorship ratios from life tables to the number of 20 year-old males in 2016. This calculation is performed for all ages and both sexes to obtain a 'survived' population for 2017;
• net interstate migration (by single year of age and sex) for 2017 was derived by applying migration rates to the 2016 Aboriginal and Torres Strait Islander population and adding these to the population at the relevant geography (that is, state or territory population, Remoteness Area or Indigenous Region); and,
• to project the number of 0 year-olds in 2017, assumed age-specific fertility and paternity rates were applied to the male and female populations (respectively) aged 15-49 years to project total number of births for 2017. These births were then split into males and females using an assumed sex ratio at birth. Since some of these births will die before reaching age 0, life table 'survival probability from birth age 0' was finally applied to project the population at age 0 for each sex separately.

33 The result of these steps is the projected population for 2017. This process is repeated to produce each successive year of the projection, until the year 2031.

### Confidentiality

34 The Census and Statistics Act, 1905 provides the authority for the ABS to collect statistical information, and requires that statistical output shall not be published or disseminated in a manner that is likely to enable the identification of a particular person or organisation. This requirement means that the ABS must take care and make assurances that any statistical information about individual respondents cannot be derived from published data.

35 Some techniques used to guard against identification or disclosure of confidential information in statistical tables are suppression of sensitive cells, random adjustments to cells with very small values, and aggregation of data. To protect confidentiality within this release, some cell values may have been suppressed and are not available for release but included in totals where applicable. In these cases data may not sum to totals due to the confidentialisation of individual cells.

### Rounding

36 In this release population estimates and projections, and their components have sometimes been rounded. Rounded figures and unrounded figures should not be assumed to be accurate to the last digit shown. Where figures have been rounded, discrepancies may occur between sums of component items and totals.

### Acknowledgements

37 ABS publications draw extensively on information provided freely by individuals, businesses, governments and other organisations. Their continued cooperation is very much appreciated; without it, the wide range of statistics published by the ABS would not be available. Information received by the ABS is treated in strict confidence as required by the Census and Statistics Act, 1905.

38 As well as the statistics included in this and related publications, the ABS may have other relevant data available on request. Inquiries should be made to the National Information and Referral Service on 1300 135 070.

39 ABS products and publications are available free of charge from the ABS web site http://www.abs.gov.au. Click on Statistics to gain access to the full range of ABS statistical and reference information.

## Glossary

### Show all

#### Aboriginal and Torres Strait Islander birth

The birth of a live-born child where either the mother or the father was identified as being of Aboriginal or Torres Strait Islander origin on the birth registration form.

#### Aboriginal and Torres Strait Islander death

Registration of deaths is the responsibility of the state and territory Registries of Births, Deaths and Marriages. Information about the deceased is acquired from a Death Registration Form (DRF). All states and territories use information from DRF to identify an Aboriginal and Torres Strait Islander death.

In addition, some states and territories also use the Medical Certificate of Cause of Death (MCCD) to identify an Aboriginal and Torres Strait Islander death. 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. If the Indigenous status reported in the DRF does not agree with that in the MCCD, an identification from either source that the deceased was an Aboriginal and/or Torres Strait Islander person is given preference over non-Indigenous.

#### Age heaping

The phenomenon of uneven population age distribution in Census or survey data. When age heaping occurs, data show systematic spikes on particular ages such as those ending in 0 or 5. This happens as a result of 'digit preference' or rounding when respondents are unsure of their age or the age of others they are reporting on behalf of. An age heaping adjustment was applied to the population of the Northern Territory, as part of compiling the final 30 June 2016 ERP based on the 2016 Census.

#### Age-sex pyramid

A bar chart graphically representing the age structure of the population, usually in five-year age groups, for males and females separately. The age structure of the population usually approximates the shape of a pyramid because mortality progressively reduces the number in each birth cohort as it ages. The age pyramid is useful to show the existence of unusually large or small cohorts, and in this way, not only conveys information about a country's past demographic history, but also a great deal about its demographic future.

#### Age-specific death rates

The number of deaths (either occurred or registered) during the calendar year at a specified age per 1,000 of the estimated resident population of the same age at the mid-point of the year (30 June). Pro rata adjustment is made in respect of deaths for which the age of the deceased is not given.

#### Age-specific fertility rates

The number of live births (either occurred or registered) during the calendar year, according to the age of the mother, per 1,000 of the female estimated resident population of the same age at 30 June. In the calculation of these rates, births to mothers under 15 years are included in the 15-19 years age group, and births to mothers aged 50 years and over are included in the 45-49 years age group. Pro rata adjustment is made for births for which the age of the mother is not given.

#### Age-specific paternity rates

The number of live births (either occurred or registered) during the calendar year, according to the age of the father, per 1,000 of the male estimated resident population of the same age at 30 June. In the calculation of these rates, births to fathers under 15 years are included in the 15-19 years age group, and births to fathers aged 50 years and over are included in the 45-49 years age group. Pro rata adjustment is made for births for which the age of the father is not given.

#### Average annual growth rate

The average annual growth rate, r, is calculated as a percentage using the formula:

$$\large{r =\left[\left(\frac{p_n}{p_0}\right)^{\frac{1}{n}}-1\right] \times 100}$$

where $$P_o$$ is the population at the start of the period, $$P_n$$ is the population at the end of the period and $$n$$ is the length of the period between $$P_o$$ and $$P_n$$ in years.

#### Birth

The delivery of a child, irrespective of the duration of pregnancy, who, after being born, breathes or shows any evidence of life such as heartbeat.

#### Completed fertility

Completed fertility represents the average number of births a cohort of females have borne over their reproductive lifetimes.

#### Death

The permanent disappearance of all evidence of life after birth has taken place. The definition excludes all deaths prior to live birth. For the purposes of the ABS Death Registration collection, a death refers to any death which occurs in, or en route to Australia and is registered with a state or territory Registry of Births, Deaths and Marriages.

#### Estimated resident population (ERP)

The official measure of the population of Australia is based on the concept of usual residence. It refers to all people, regardless of nationality, citizenship or legal status, who usually live in Australia, with the exception of foreign diplomatic personnel and their families. It includes usual residents who are overseas for less than 12 months over a 16 month period. It excludes overseas visitors who are in Australia for less than 12 months over a 16 month period.

Estimates of the Australian resident population are generated on a quarterly basis by adding natural increase (the excess of births over deaths) and net overseas migration (NOM) occurring during the period to the population at the beginning of each period.

#### Indigenous Region (IREG)

Indigenous Regions (IREGs) are large geographical units loosely based on the former Aboriginal and Torres Strait Islander Commission boundaries. They are created by aggregating one or more Indigenous Areas.

#### Intercensal period

The time period between 30 June in the previous Census year and 30 June of the latest Census year.

#### Life expectancy

The average number of additional years a person of a given age and sex might expect to live if the age-specific death rates of each period continued throughout his/her lifetime.

#### Life table

A tabular, numerical representation of mortality and survivorship of a cohort of births at each age of life. The conventional life table is based on the assumption that as the cohort passes through life it experiences mortality at each age in accordance with a predetermined pattern (usually based upon death rates from a real population during a particular period of time) of mortality rates which do not change from year to year. The life table thus constitutes a hypothetical model of mortality, and it does not describe the actual mortality which characterises a cohort as it ages.

Life tables may be complete or abridged, depending on the age interval used in their compilation. Complete life tables such as those for the Australian population contain data by single years of age, while abridged life tables, such as those for the Aboriginal and Torres Strait Islander population, contain data for five-year age groups. Due to differences in mortality patterns between males and females at different ages, life tables are generally constructed separately for each sex.

#### Median age

For any distribution the median value is that which divides the relevant population into two equal parts, half falling below the value, and half exceeding it. Thus, the median age is the age at which half the population is older and half is younger.

#### Migration

The movement of people across a specified boundary for the purpose of establishing a new or semi-permanent residence. Migration can be international (migration between countries) and internal (migration within a country).

#### Mortality differentials

The difference in mortality when comparing one population group with another. In this release, it is calculated as the ratio of life expectancy at birth for a particular geographic region (e.g. state/territory) over the life expectancy at birth for Australia.

#### Natural increase

Excess of births over deaths.

#### Net interstate migration

Net interstate migration is the net gain or loss of population though interstate migration being the change of a person's place of usual residence from one state or territory to another state or territory.

#### Net overseas migration

Net overseas migration is the net gain or loss of population through immigration to Australia and emigration from Australia.

#### Net population growth

For Australia, net population growth is the sum of natural increase and net overseas migration. For the states and territories, net population growth also includes net interstate migration.

#### Net undercount

The difference between the actual Census count (including imputations) and an estimate of the number of people who should have been counted in the Census. This estimate is based on the Post Enumeration Survey (PES) conducted after each Census. For a category of person (e.g. based on age, sex and state of usual residence), net undercount is the resultant of Census undercount, overcount, misclassification and imputation error.

#### Other territories

Following the 1992 amendments to the Acts Interpretation Act to include the Indian Ocean Territories of Christmas Island and the Cocos (Keeling) Islands as part of geographic Australia, another category of the state and territory level has been created, known as Other Territories. Other Territories include Jervis Bay Territory, previously included with the Australian Capital Territory, as well as Christmas Island, the Cocos (Keeling) Islands and Norfolk Island.

#### Post Enumeration Survey (PES)

The Census Post Enumeration Survey (PES) is a household survey conducted following the Census. The PES allows the ABS to estimate the number of people missed in the Census and the number counted more than once or in error. Results from the PES contribute to a more accurate calculation of the estimated resident population (ERP) for Australia and the states and territories, which is then backdated to 30 June of the Census year.

#### Remoteness Area

An aggregation of non-continuous geographical areas which share common characteristics of remoteness. The delimitation criteria for Remoteness Areas (RAs) are based on the Accessibility/Remoteness Index of Australia (ARIA+) which measures the remoteness of a point based on the road distance to the nearest urban centre. The RA categories range from Major Cities to Very Remote. Within the Australian Statistical Geography Standard, each RA is created from a grouping of Statistical Areas Level 1 having a particular degree of remoteness.

#### Sex ratio

The number of males per 100 females.

#### State/territory of usual residence

State or territory of usual residence refers to the state or territory of usual residence of:

• the population
• the mother (Birth Registrations collection) and
• the deceased (Death Registrations collection).

#### Total fertility rate (TFR)

The sum of age-specific fertility rates expressed as rate per woman. It represents the number of children a female would bear during her lifetime if she experienced current age-specific fertility rates at each age of her reproductive life.

#### Total paternity rate (TPR)

The sum of age-specific paternity rates expressed as a rate per man. It represents the number of children a male would father during his lifetime if he experienced current age-specific paternity rates at each age of his reproductive life.

#### Unexplained growth

The intercensal growth in the Aboriginal and Torres Strait Islander population counts that cannot be fully explained by births, deaths and migration.

## Quality declaration

### Institutional environment

Australian Bureau of Statistics (ABS) estimates and projections of the Aboriginal and Torres Strait Islander population of Australia are based on population estimates derived from the most recent Census of Population and Housing (currently 2016) and Post Enumeration Survey as well as data from the birth and death registration collections. Assumptions about past and future levels of the components of population change are applied to the base Census population in order to produce estimates (for earlier reference years) and projections (for future reference years).

Assumptions are derived from an analysis of data sourced form a variety of institutional environments. Much of this data is administrative by-product data collected by other organisations. Assumptions on fertility and mortality are based on births and deaths statistics extracted from registers administered by the various state and territory registrars of births, deaths and marriages.

For information on the institutional environment of the Australian Bureau of Statistics (ABS), including the legislative obligations of the ABS, financing and governance arrangements, and mechanisms for scrutiny of ABS operations, please see ABS Institutional Environment .

### Relevance

Aboriginal and Torres Strait Islander population estimates for years prior to the base population provide estimates on a temporally consistent basis, thus eliminating any inconsistencies in estimates due to the changing propensity of people to identify as Aboriginal and Torres Strait Islander across Censuses or changes to the methods used to collect this information. Estimates are published for Australia and the states/territories, by five-year age groups and sex. Single year of age data is also available for persons only.

Population projections inform on future changes in the Aboriginal and Torres Strait Islander population of Australia, such as population growth/decline and changes in age structure, and are therefore used in a variety of key planning decisions. Projections are published for Australia, states/territories, Indigenous Regions and three categories of Remoteness Areas, by five-year age groups and sex. Single year of age data is also available for Australia, states/territories and three categories of Remoteness Areas for persons only.

Assumptions have been formulated on the basis of past demographic trends, in conjunction with consultation with various experts and government department representatives at the national and state/territory level.

### Timeliness

ABS Aboriginal and Torres Strait Islander population estimates and projections are compiled and published once every five years (i.e. after each Census of Population and Housing).

### Accuracy

#### Base population (2016 estimates)

The estimates and projections presented in this release are based on results of the 2016 Census of Population and Housing, adjusted for net undercount as measured by the Post Enumeration Survey (PES). The goal of the Census is to obtain a complete measure of the number, and characteristics, of people in Australia on Census night and their dwellings.

The ABS conducts the PES shortly after the Census to determine how many people were missed in the Census and how many were counted more than once. For 2016, the net undercount of the Aboriginal and Torres Strait Islander population was 137,750 persons (17.5%). The extent of undercoverage of Aboriginal and Torres Strait Islander Australians in the 2016 Census, the relatively small sample size of the PES to adjust for the undercoverage, and the number of records with unknown Indigenous status means that 2016 population estimates should be interpreted with caution. For more information see Estimates of Aboriginal and Torres Strait Islander Australians, June 2016 (cat. no. 3238.0.55.001).

It is important to remember that while the Census, PES and other administrative datasets used in compiling these estimates produce statistics with relatively small amounts of error, this error can be more significant when focussing on a very small population (like the Aboriginal and Torres Strait Islander population).

#### Population estimates

Given that the quality of historical Aboriginal and Torres Strait Islander component data (births, deaths and migration) is variable, ABS Aboriginal and Torres Strait Islander population estimates for non-Census years are produced by applying assumptions about past levels of Aboriginal and Torres Strait Islander life expectancy and net interstate migration at birth to the population. As levels of life expectancy at birth are unknown, estimates should be treated with caution, particularly for the period 2001 to 2005.

Aboriginal and Torres Strait Islander population estimates for 2001 to 2015 based on the 2016 Census supersede previously published estimates for this period.

#### Population projections

ABS Aboriginal and Torres Strait Islander population projections are based on a number of assumptions on future levels of fertility, mortality and migration. They are not intended as predictions or forecasts, but are illustrative of growth and change in the Aboriginal and Torres Strait Islander population that would occur if the assumptions were to prevail over the projection period.

While the assumptions are formulated on the basis of an assessment of past demographic trends, there is no certainty that any of the assumptions will be realised. In addition, the assumptions do not attempt to allow for non-demographic factors (such as major government policy decisions, economic factors, natural disasters, epidemics or significant health treatment improvements) which may affect future demographic behaviour or outcomes.

The accuracy of each component of the data presented in this release is also affected by changing social norms and an individual's propensity to identify as an Aboriginal and Torres Strait Islander Australian. This propensity is not only affected by an individual's decision on how they choose to identify, but also by improvements to collections methods that allow the data to be captured more accurately. This propensity can change over time and between collections, which can significantly affect the accuracy of the data.

### Coherence

The estimates and projections presented in this release are not consistent with estimates and projections based on 2011 or previous Censuses. As the assumptions used in each successive set of Aboriginal and Torres Strait Islander population estimates and projections incorporate recent trends, comparison of data across issues of this release is not advised. As mentioned above, the coherence of this data is also affected an individual's propensity to identify in each collection and the ability of each dataset to accurately capture this information which can vary across time and between data sources. The coherence between the estimates and projections compiled at different points in time is explored in more detail on the page: Guide to using historical estimates for comparative analysis and reporting.

### Interpretability

ABS population projections are not intended as predictions or forecasts, and should not be considered as such. Rather, they are illustrations of growth and change in the population that would occur if the assumptions were to prevail over the projection period.

This release contains information about the assumptions and methods used to produce the Aboriginal and Torres Strait Islander population estimates and projections. It also contains Explanatory Notes and Glossary that provide information on the data sources, terminology, classifications and other technical aspects associated with these statistics and their use.

### Accessibility

ABS Aboriginal and Torres Strait Islander population projections are available in a variety of formats on the ABS web site under the 3238.0 product family. The formats available are:

• Main Features, which contains commentary on key figures
• Datacubes (in excel and ABS.Stat formats) containing:

• Aboriginal and Torres Strait Islander population estimates and projections for Australia and the states and territories, by five-year age groups to 85 years and over (65 years and over for Tasmania and the Australian Capital Territory), and sex, for all projection series ( Series A-I);
• Aboriginal and Torres Strait Islander population projections for Indigenous Regions, by five-year age groups (to 65 years and over) and sex (Series A, B and C);
• Aboriginal and Torres Strait Islander population projections for Remoteness Areas, by five-year age groups (to 75 years and over) and sex (Series A, B and C).
• data cubes containing Aboriginal and Torres Strait Islander population projections, components of change and summary statistics for Australia and the states and territories, Indigenous Regions and Remoteness Areas, for the three main projection series (Series A, B and C).

If the information you require is not available as a standard product, then ABS Consultancy Services can help you with customised services to suit your needs. For inquiries contact the National Information Referral Service on 1300 135 070 or email client.services@abs.gov.au.

The ABS observes strict confidentiality protocols as required by the Census and Statistics Act, 1905. This may limit access to data at a detailed level.

## Bibliography

### Show all

ABS and AIHW 2012, The Health and Welfare of Australia's Aboriginal and Torres Strait Islander Peoples, cat. no. 4704.0, ABS, Canberra.

ABS 2014, Estimates and Projections, Aboriginal and Torres Strait Islander Australians, 2001 to 2026, cat. no. 3238.0. ABS, Canberra.

ABS 2018, Census of Population and Housing: Understanding the Increase in Aboriginal and Torres Strait Islander Counts, 2016, cat. no. 2077.0, ABS, Canberra.

ABS 2018, Estimates of Aboriginal and Torres Strait Islander Australians, June 2016, cat. no. 3238.0.55.001, ABS, Canberra.

ABS 2018, Life Tables for Aboriginal and Torres Strait Islander Australians, 2015-2017, cat. no. 3302.0.55.003, ABS, Canberra.

ABS 2018, Population Projections, Australia, 2017 (base) - 2066, cat. no. 3222.0, ABS, Canberra.

ABS various years, Births, Australia, cat. no. 3301.0, ABS, Canberra

ABS various years, Deaths, Australia, cat. no. 3302.0, ABS, Canberra.

Wilson T, Condon JR and Barnes T 2007, Northern Territory Indigenous Life Expectancy Improvements, 1967-2004, Australian and New Zealand Journal of Public Health, vol. 31, no. 2, pp 184-8.

## Abbreviations

### Show all

 ABS Australian Bureau of Statistics ACT Australian Capital Territory ASDR age-specific death rate ASFR age-specific fertility rate ASGS Australian Statistical Geography Standard Aust. Australia ERP estimated resident population IREG Indigenous Region NSW New South Wales NT Northern Territory OT Other Territories PES Census of Population and Housing Post Enumeration Survey Qld Queensland RA Remoteness Area SA South Australia Tas. Tasmania TFR total fertility rate Vic. Victoria WA Western Australia