3222.0 - Population Projections, Australia, 2012 (base) to 2101 Quality Declaration 
ARCHIVED ISSUE Released at 11:30 AM (CANBERRA TIME) 26/11/2013   
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ASSUMPTIONS

INTRODUCTION

The Australian Bureau of Statistics (ABS) uses the cohort-component method for producing population projections. In this method, assumptions made about future levels of fertility, mortality, overseas migration and internal migration are applied to a base population (split by sex and single year of age) to obtain a projected population for the following year. The assumptions are then applied to this new (projected) population to obtain a projected population for the next year. This process is repeated until the end of the projection period is reached.

Span of projections

From a base of 30 June 2012, the projections span the period 30 June 2013 to 30 June 2101 for Australia, and 30 June 2013 to 30 June 2061 for the states, territories, capital cities and balances of state. Estimated resident population (ERP) for 30 June 2012 for all above mentioned geographies have also been included in the data.


SUMMARY OF ASSUMPTIONS

Assumptions have been formulated on the basis of demographic trends over the past decade and longer, both in Australia and overseas, in conjunction with consultation with experts at the national and state/territory level. They do not specifically attempt to allow for non-demographic factors (such as major government policy decisions, economic factors, catastrophes, wars, epidemics or significant health treatment improvements) which may affect future demographic behaviour or outcomes.

As future levels of fertility, mortality, overseas migration and internal migration are unpredictable, two or more assumptions have been made for each component. These are intended to illustrate a range of possible future outcomes, although there can be no certainty that any particular outcome will be realised, or that future outcomes will necessarily fall within these ranges.

Diagram: SUMMARY OF ASSUMPTIONS

The table below shows how recent demographic trends (an average of the last three years) relate to the proposed assumptions. The component which diverges from recent history the most is net overseas migration (NOM), and as a consequence, the last three years of average growth has been higher than the Department of Immigration and Border Protection's (DIBP) forecasts.

The projections will show a smooth transition from the most recently observed data to the long-range assumption. This 'phase-in' period is different for each component assumption and so the table also shows the year that each assumption will be phased in by.

Population projections, Summary of assumptions

Observed average
Medium assumption
Phased in by

Total fertility rate(a)
1.9
1.8
2025-26
Life expectancy at birth(b)(c)
Male
79.7
85.2
2060-61
Female
84.2
88.3
2060-61
Net overseas migration(a)
199 860
240 000
2020-21
Average annual growth rate(a)
1.6
. .
. .

. . not applicable
(a) Observed average of financial years 2010-2012.
(b) Observed average of calendar years 2009-2011.
(c) Note that the Australia level projections go out to 2101.



Fertility

For the fertility component, assumptions are made about future total fertility rates (TFRs), age-specific fertility rates (ASFRs) and the sex ratio at birth. Three long-term assumptions have been made about Australia's future levels of fertility:
  • high: the TFR will reach 2.0 babies per woman by 2026, and then remain constant;
  • medium: the TFR will decline to 1.8 babies per woman by 2026, and then remain constant; and
  • low: the TFR will decline to 1.6 babies per woman by 2026, and then remain constant.

The trend towards older mothers at birth is assumed to continue to 2026, but at a slower rate than historical trends, and remain constant thereafter. The sex ratio at birth is assumed to be 105.5 male births per 100 female births for all years.

Mortality

For the mortality component, assumptions are made about future levels of life expectancy at birth for males and females. Two assumptions have been made:
  • High life expectancy at birth (continued improvement) is assumed for male and female life expectancy, with increases from 2009-11 levels of 0.25 and 0.19 years respectively, until 2060-61. Based on this assumption, male life expectancy would reach 92.1 years in 2060-61 and female life expectancy would reach 93.6 years.
  • Medium life expectancy at birth (declining improvement) is assumed for male and female life expectancy at birth, with increases of 2009-11 levels by 0.25 and 0.19 years respectively until 2015-16. After this, life expectancy will continue to increase at declining rates. Based on this assumption, male life expectancy at birth is expected to reach 85.2 years in 2060-61 and female life expectancy to reach 88.3 years.

Under both assumptions, the pattern of change in age-sex specific death rates has been assumed to continue until 2031. Thereafter, the age-specific death rates are uniformly scaled to conform to the assumed life expectancy at birth for future years.

Overseas migration

Three main assumptions and one 'what-if' assumption have been made about Australia's future levels of net overseas migration (NOM):
  • high: NOM will increase to 280,000 people per year by 2020-21 and remain constant thereafter;
  • medium: NOM will increase to 240,000 people per year by 2020-21 and remain constant thereafter; and
  • low: NOM will increase to 200,000 people per year by 2020-21 and remain constant thereafter.
  • A zero net overseas migration assumption has been included to facilitate analysis of the effect of overseas migration on Australia's future population.

Interstate migration

Three assumptions have been made about future net interstate migration levels:
  • large interstate flows: relatively large net interstate migration gains for some states and territories, corresponding to relatively large losses for other states and territories;
  • medium interstate flows: medium net interstate migration gains for some states and territories, and medium losses for others; and
  • small interstate flows: relatively small net interstate migration gains for some states and territories, and small losses for others.


BASE POPULATION

The base population is the preliminary estimated resident population (ERP) at 30 June 2012, which takes into account the 2011 Census of Population and Housing.


PROJECTION SERIES

The above assumptions can be combined to create 54 sets of population projections. Three main series have been selected from these to provide a range, although not the full range, of projections for analysis and discussion in Chapter 3. These series are referred to as Series A, B and C. At times, to simplify the analysis, Series B has been chosen.

For some states, Series A and C do not depict the highest or lowest population outcomes. Where applicable, other series have been included in commentary.

The inclusion of a zero net overseas migration assumption increases the total number of available projections to 72 series, as presented on the following page. These extra series (Series 55 to 72) have not been considered for analysis in this publication but are included in data cubes attached to this publication.


WHICH SERIES TO USE

Future uncertainty, along with the subjective nature of assessing current trends, means that using a range of possible outcomes rather than a single projection series give a more realistic view of the possible future size, distribution and age structure of Australia's population.

Different series, constructed from varying combinations of assumptions, are appropriate for different time horizons (shorter or longer term), the geographic region(s) considered, and any volatility in the components. All series are relatively insensitive to future levels of fertility and mortality, as both are fairly predictable. There is less certainty regarding future levels of overseas and interstate migration, due to their historical volatility. This volatility can be expected to continue due to future government policies and decision making, and economic, social and other determinants and influences in Australia and overseas.

The following table presents the 72 permutations of the various assumptions considered in developing the range of projections, with series A, B and C specifically identified.

Projection series, Assumptions used

High life expectancy
at birth
Medium life expectancy
at birth
Net overseas migration
Net interstate migration (large flows)(a)
Net interstate migration (medium flows)
Net interstate migration (small flows)(a)
Net interstate migration (large flows)(a)
Net interstate migration (medium flows)
Net interstate migration (small flows)(a)

HIGH FERTILITY (2.0)

280 000
1(A)
2
3
4
5
6
240 000
19
20
21
22
23
24
200 000
37
38
39
40
41
42
0
55
56
57
58
59
60

MEDIUM FERTILITY (1.8)

280 000
7
8
9
10
11
12
240 000
25
26
27
28
29(B)
30
200 000
43
44
45
46
47
48
0
61
62
63
64
65
66

LOW FERTILITY (1.6)

280 000
13
14
15
16
17
18
240 000
31
32
33
34
35
36
200 000
49
50
51
52
53
54(C)
0
67
68
69
70
71
72

(a) The large interstate flows assumption corresponds to large net interstate losses for New South Wales, South Australia and the Northern Territory, where the small interstate flows assumption yields greater population growth.



FERTILITY ASSUMPTIONS

Summary

Future trends in fertility are an important determinant of Australia's future population size, structure and growth. To produce population projections using the cohort-component method, assumptions for each year of the projection period are required for age-specific fertility rates and the sex ratio at birth.

Three long-term assumptions have been made regarding Australia's future TFR: high fertility (a TFR of 2.0 babies per woman), medium fertility (1.8) and low fertility (1.6). Under all three assumptions, the trend towards older ages of mothers at birth of children is assumed to continue to 2026, but at a slower rate than historical trends, and remain constant thereafter. For all years, the sex ratio at birth is assumed to be 105.5 male births per 100 female births.

Trends in the total fertility rate

In 1961, at the height of the 'baby boom', Australia's TFR peaked at 3.5 babies per woman. Since then fertility has declined, falling sharply during the early 1960s, before levelling out at around 2.9 babies per woman in the years 1966-1971. The TFR reached replacement level (2.1) in 1975, and continued to fall. Fertility stabilised somewhat during the 1980s, before resuming a more gradual decline during the 1990s. The TFR reached a low of 1.7 babies per woman in 2001 and has increased since then, to 1.9 babies per woman in 2011.

Total fertility rate(a), Australia
Graph: Total fertility rate(a), Australia



Assumed total fertility rates

The three assumptions for Australia's future fertility levels are made with regard to recent trends in the TFR, especially those of the last decade.

The high fertility scenario assumes that Australia's TFR will reach 2.0 babies per woman by 2026 and remain constant thereafter. This reflects levels of fertility recorded since 1977 of between 1.7 and 2.0 babies per woman, acknowledging the possibility that the TFR could increase more, especially in the short-term.

The medium scenario assumes a short-term continuation of the increase in fertility since 2001, with the TFR increasing to 1.9 babies per woman in 2013, then gradually decreasing to 1.8 by 2026 and remaining constant thereafter.

Under the low fertility assumption the TFR remains constant in 2013, followed by a decline at a faster rate, reaching 1.6 babies per woman by 2026 and remaining constant thereafter. Fertility rates have reached such levels in many European countries, and recent projections indicate this is considered a possibility in several others. Within Australia, fertility in the Australian Capital Territory and Victoria reached lows of 1.56 and 1.63 respectively in 2001.

Birth registrations processed up to December quarter 2011 present a continuation of the recent rise in fertility, however the size and duration of the rise is not possible to gauge. Recent government policy initiatives and public attention and discussion of the impacts of lower fertility may have an effect in mitigating any future declines in fertility.

Total fertility rate(a), Australia - Observed and assumed
Graph: Total fertility rate(a), Australia—Observed and assumed



Trends in age-specific fertility rates

Population projections require assumptions about future age-specific fertility rates, which are derived from assumed TFRs and age distributions of fertility. These rates are applied to the projected female population in each year of the projection period in order to determine future numbers of births, and therefore the size of future projected populations.

Over the past 10 years, age-specific fertility rates have been declining for the younger age groups (women below age 30), whilst increasing among women aged 30 years and over, representing a gradual shift in fertility towards older ages.

The projected age distribution of fertility is based on average annual rates of change in age-specific fertility rates during the period 2007-2011. These historical trends are assumed to continue under all three fertility scenarios until 2026, after which the age pattern of fertility remains constant.

Linear interpolation is employed to obtain TFRs for each year 2012 to 2026 for all three scenarios. The assumption of continuing deferment of fertility is calculated by applying the average annual change in the percentage age distribution of fertility over the five year period, 2007-2011 to the base distribution, to obtain the assumed age distribution of fertility in a projection year. The assumed distribution is then applied to the assumed TFR for the corresponding projection year.

Age-specific fertility rates(a), Australia - Observed and assumed
Graph: Age-specific fertility rates(a), Australia—Observed and assumed



Sex ratio at birth

Projections require an assumed sex ratio at birth (the ratio of male to female births, multiplied by 100), so that total projected births can be split into male and female births.

The sex ratio fluctuates around 105 to 105.5 males births per 100 female births. The sex ratio was 105.3 for the year ended 30 June 2011, 105.1 in 2006, and 105.4 in 2001. A constant ratio of 105.5 male births per 100 female births has been used for the duration of the projection period.

State/territory and capital city/balance of state fertility assumptions

The table below shows the TFRs for all states and territories and Australia from 1991 to 2011. Some states have consistently been higher or lower than the national rate, while others have fluctuated over the past 20 years. In recent years, TFRs for Victoria, South Australia and the ACT have been lower than rates for Australia as a whole, while TFRs for the remaining states and territories, particularly Tasmania and the Northern Territory, have been higher.

State and territory total fertility rates, Observed

1991
1996
2001
2006
2011

New South Wales
1.93
1.80
1.79
1.80
1.97
Victoria
1.83
1.72
1.63
1.74
1.80
Queensland
1.90
1.83
1.84
1.94
2.02
South Australia
1.74
1.73
1.69
1.79
1.87
Western Australia
1.93
1.80
1.75
1.90
1.93
Tasmania
1.93
1.85
1.87
2.09
2.12
Northern Territory
2.30
2.19
2.20
2.23
2.12
Australian Capital Territory
1.82
1.62
1.56
1.66
1.74
Australia
1.88
1.78
1.75
1.83
1.93



The ratio of each state and territories' average TFR for the three years 2009-2011 to that of Australia is calculated, then applied to assumed future Australia-level TFRs. However, in some states these ratios have been adjusted to incorporate more recent data as it becomes available (for example, 2012 data). The resulting set of state to Australia fertility differentials are thus calibrated to give projected births that are consistent with latest historical levels and trends. These differentials are assumed to remain constant throughout the projection period.

TFRs for Australian capital cities are typically lower than TFRs for their respective states and territories, while TFRs for state balances are higher. In 2011, the TFR for Brisbane was 9% lower than the TFR for Queensland, while TFRs for Darwin, Sydney and Perth were 6-8% lower than their respective states. TFRs for Adelaide and Melbourne were 4-5% lower than South Australia and Victoria respective, while Hobart was less than 3% lower than Tasmania.

Assumed TFRs for the capital cities and state balances are derived by applying the average differential (for 2009-2011) between the region and its respective state/territory to that state/territory's assumed TFR. Similar to the state to Australia differentials, the capital city/balance of state to state/territory differentials were calibrated, where necessary, to ensure projected births were consistent with recent trends in numbers of births.

TOTAL FERTILITY RATES AND FERTILITY DIFFERENTIALS

TOTAL FERTILITY RATE(a)(b)
ASSUMED FERTILITY DIFFERENTIAL(c)
Capital city
Balance of state
Total
Capital city
Balance of state
Total
rate
rate
rate
%
%
%

New South Wales
1.84
2.06
1.92
96.2
107.5
99.5
Victoria
1.74
2.08
1.81
96.2
114.8
93.9
Queensland
1.88
2.05
2.07
96.0
104.6
107.6
South Australia
1.77
2.20
1.90
93.1
115.9
98.6
Western Australia
1.83
2.18
1.95
93.9
111.6
101.2
Tasmania
2.03
2.12
2.12
95.9
100.3
109.9
Northern Territory
1.94
2.31
2.13
91.0
108.6
111.6
Australian Capital Territory
. .
. .
1.76
. .
. .
91.4
Australia(d)
. .
. .
1.97
. .
. .
100.0

. . not applicable
(a) Babies per woman.
(b) Average of 2009, 2010 and 2011 TFRs.
(c) Assumed fertility differentials show the relationship of the average TFR for 2009-2011 for each state/territory, capital cityand balance of state to the Austalian level. Includes adjustments to ensure projected births are consistent with recent trends in numbers of births.
(d) Includes Other Territories.

ASSUMED TOTAL FERTILITY RATES(a), From 2026 - States and territories

HIGH ASSUMPTION
MEDIUM ASSUMPTION
LOW ASSUMPTION
Capital
city
Balance
of state
Total
Capital
city
Balance
of state
Total
Capital
city
Balance
of state
Total
rate
rate
rate
rate
rate
rate
rate
rate
rate

New South Wales
1.92
2.14
1.99
1.72
1.93
1.79
1.53
1.71
1.59
Victoria
1.81
2.16
1.88
1.63
1.94
1.69
1.45
1.73
1.50
Queensland
2.07
2.25
2.15
1.86
2.03
1.94
1.65
1.80
1.72
South Australia
1.84
2.29
1.97
1.65
2.06
1.78
1.47
1.83
1.58
Western Australia
1.90
2.26
2.03
1.71
2.03
1.82
1.52
1.81
1.62
Tasmania
2.11
2.20
2.20
1.90
1.98
1.98
1.69
1.76
1.76
Northern Territory
2.03
2.42
2.23
1.83
2.18
2.01
1.62
1.94
1.79
Australian Capital Territory
. .
. .
1.83
. .
. .
1.65
. .
. .
1.46
Australia(b)
. .
. .
2.00
. .
. .
1.80
. .
. .
1.60

. . not applicable
(a) Babies per woman.
(b) Includes Other Territories.


International context

Fertility levels vary considerably between countries. There are many factors that can influence a country's fertility rate, such as differences in social and economic development and contraceptive prevalence. In general, developing countries have higher fertility rates while developed countries have lower fertility rates. According to the Population Reference Bureau (PRB) 2013 World Population Data Sheet, more-developed countries have an average TFR of 1.6 babies per woman, while less-developed countries have an average TFR of 2.6.

Australia's TFR for 2011 of 1.9 babies per woman is well below the PRB world average of 2.5 babies per woman. Compared to other developed countries, Australia's TFR is above the PRB average of 1.6. Fertility in Hong Kong is very low at 1.3 babies per woman. Other countries that have low fertility are Andorra (1.2) and Hungary, Poland, Spain and Taiwan (all with 1.3). In contrast, many African countries have very high fertility rates, with Niger (7.6) and Angola (6.3) among the highest.

International fertility rates provide a frame of reference for the three fertility assumptions made for Australia. A TFR of 2.0 as assumed under the high fertility scenario equates to the current fertility level in countries such as New Zealand, the United Kingdom and Iceland (all 2.0). The medium fertility scenario (a TFR of 1.8) would bring Australian fertility into line with current levels in countries such as Norway and Belgium. Australia's assumed TFR for the low fertility scenario (1.6) is the current average for the more developed countries.


MORTALITY ASSUMPTIONS

Summary

For the population projections in this issue, two assumptions on future life expectancy at birth, a key measure of mortality, have been made. Only two assumptions have been made because life expectancy has consistently shown an improving trend since Australian records began. This historical trend is linear at around 25 years of life expectancy improvement over the last hundred years. The international discussion among demographic experts on the future of mortality is focused on the two scenarios of this long-run historical trend of life expectancy improvement continuing or declining.

The high life expectancy at birth assumption assumes that life expectancy will continue to improve at the historical rate, resulting in assumed life expectancy at birth of 92.1 years for males and 93.6 years for females in 2061. The medium life expectancy at birth assumption assumes that life expectancy will continue to improve at the historical rate until 2016, and then gradually slow to result in assumed life expectancy at birth of 85.2 years for males and 88.3 years for females in 2061.

Assumptions for mortality at lower level geographical levels are based on 2009-2011 differentials between Australia and each state/territory, and between each state/territory and its capital city/balance of state. These differentials remain constant throughout the projection series.

Trends in life expectancy

Australian life expectancy at birth has improved steadily for both men and women. Male life expectancy at birth increased from 55.2 years in the period 1901-1910 to 79.7 years in 2009-2011. Over the same period female life expectancy increased from 58.8 years to 84.2 years.

The past two decades have seen further improvements in life expectancy. These increases are due in part to lower infant mortality, fewer deaths among children and young adults from accidents and improvements in cardiovascular health among older men (AIHW 2013).

LIFE EXPECTANCY AT BIRTH, Australia
Graph: LIFE EXPECTANCY AT BIRTH, Australia


Between 1982 and 2009-2011, life expectancy at birth has improved on average by 0.3 years per year for males and 0.2 years per year for females. For both males and females, the smallest increase during this period was recorded between 2006-2008 (with male life expectancy increasing by 0.14 years and female life expectancy increasing by 0.04 years) while the largest growth was recorded between 1982 and 1983 (with male life expectancy increasing by 0.89 years and female life expectancy increasing by 0.52 years).

LIFE EXPECTANCY AT BIRTH, 1982 to 2009-2011

Life expectancy at birth
Increase per year(a)
Males
Females
Males
Females
Difference between female and male life expectancy
years
years
years
years
years

1982
71.25
78.26
. .
. .
7.0
1986
72.88
79.20
0.48
0.37
6.3
1991
74.40
80.41
0.53
0.33
6.0
1994-1996(b)
75.22
81.05
0.27
0.21
5.8
1999-2001(b)
77.03
82.41
0.47
0.37
5.4
2000-2002(b)
77.40
82.59
0.37
0.18
5.2
2001-2003(b)
77.76
82.84
0.36
0.25
5.1
2002-2004(b)
78.08
83.03
0.32
0.19
4.9
2003-2005(b)
78.47
83.34
0.39
0.32
4.9
2004-2006(b)
78.71
83.48
0.24
0.14
4.8
2005-2007(b)
79.02
83.69
0.31
0.20
4.7
2006-2008(b)
79.16
83.73
0.14
0.04
4.6
2007-2009(b)
79.34
83.89
0.17
0.16
4.5
2008-2010(b)
79.51
84.03
0.17
0.14
4.5
2009-2011(b)
79.75
84.21
0.24
0.18
4.5
Average annual increase
. .
. .
0.30
0.23
. .

. . not applicable
(a) Over previous period.
(b) Life expectancy calculated using three years of data


The faster increase in male life expectancy at birth has narrowed the gap between male and female expectation of life at birth. In 2009-2011 female life expectancy at birth exceeded male life expectancy at birth by 4.5 years, in contrast to the peak difference of 7.0 years in 1982.

Assumed life expectancy at birth

The high life expectancy assumption assumes male and female life expectancy at birth will increase from 2009-2011 levels by 0.25 and 0.19 years respectively until 2061. Based on this assumption, male life expectancy at birth would reach 92.1 years and female life expectancy at birth would reach 93.6 years in 2061.

The medium life expectancy assumption assumes male and female life expectancy at birth will increase from 2009-2011 levels by 0.25 and 0.19 years respectively until 2016. After this, life expectancy at birth is assumed to continue to increase over the projection period, but at declining rates. Based on this assumption, male life expectancy at birth would reach 85.2 years and female life expectancy at birth would reach 88.3 years in 2061.

Life expectancy at birth, Assumed - from 2016

LIFE EXPECTANCY AT BIRTH
INCREASE PER YEAR
Males
Females
Males
Females
Difference between female and male life expectancy
Period
years
years
years
years
years

Declining improvement in life expectancy (Medium assumption)

2015-16
80.83
85.06
0.25
0.19
4.23
2020-21
81.83
85.81
0.20
0.15
3.98
2025-26
82.58
86.36
0.15
0.11
3.78
2030-31
83.08
86.76
0.10
0.08
3.68
2060-61
85.18
88.26
0.07
0.05
3.08

Constant improvement in life expectancy (High assumption)

2015-16
80.83
85.06
0.25
0.19
4.23
2020-21
82.08
86.01
0.25
0.19
3.93
2025-26
83.33
86.96
0.25
0.19
3.63
2030-31
84.58
87.91
0.25
0.19
3.33
2060-61
92.08
93.61
0.25
0.19
1.53




Trends in age-specific death rates

The inputs of the mortality component into producing population projections are 'survivorship ratios' obtained from assumed future life tables. Life tables for each year in the projection period (i.e. 2012-2101) are calculated in two steps: (1) life expectancy at birth for each projection year is determined; and (2) a life table is generated which gives the desired life expectancy at birth and allows for a shift in the age curve of mortality over time.

The shifting age curve of mortality over time should ideally represent current trends in age-sex differentials continued into the future. To achieve this, rates of change indicative of recent trends for each age-sex group are incorporated in the production of the assumed life tables. Determining assumed rates of change is achieved by observing historical patterns in age-specific death rates.

Between 1991 and 2011, males aged 10-29 experienced the fasted decline in age-specific deaths rates. Males aged 65-79, female infants and females aged 15-34 also experienced notable improvements in mortality. However, death rates of males aged 40-54 years and females aged 35-49 years showed little improvement. For both males and females, the age groups 95 and over showed no improvement. In recent times (2006-2011) the fastest declines in male mortality are for those aged 20-24 years and infants in female mortality.

Rate of change in age-specific death rates

The rates of change identified as representative of recent trends in age-sex differentials, and used to generate the projected life tables, are mainly based on the 1996-2011 trend in age-specific death rates. If necessary, adjustments were made to prevent future age-specific death rates for females exceeding those for males. The assumed rates of change continue to 2025-26, after which age-specific death rates are scaled up or down to conform to the assumed life expectancy at birth for future years.

RATE OF CHANGE(a), Age-specific death rates - Males
Graph: RATE OF CHANGE(a), Age-specific death rates—Males


RATE OF CHANGE(a), Age-specific death rates - Females
Graph: RATE OF CHANGE(a), Age-specific death rates—Females



Assumed age-specific mortality rates

Age-specific mortality rates are assumed to decrease for all age groups for both males and females over the projection period. The smallest decreases are assumed to occur in the 40-54 and 85 years and over age groups for males, and the 35-49 and 85 years and over age groups for females.

Diagram: Assumed age-specific mortality rates

Diagram: Assumed age-specific mortality rates


Assumed state/territory and capital city/balance of state mortality differentials

Mortality differentials are based on an observed relationship of each state and territory and capital city/balance of state's life expectancy to the national life expectancy, calculated separately for males and females. The differentials shown here, take account of the most recent data (2009-2011). They are calculated for each of the states and territories, and between capital cities and their respective balances of state. It is assumed that the mortality differentials based on those observed during 2009-2011 between states/territories and Australia, and between capital city/balances of state/territories within states and territories will remain constant throughout the projection period.

Mortality differentials(a), State/Territory and capital city/balance of state

LIFE EXPECTANCY AT BIRTH, 2009-2011
MALE MORTALITY DIFFERENTIALS
FEMALE MORTALITY DIFFERENTIALS
Males
Females
Capital
city
Balance
of state
State/
territory
Capital
city
Balance
of state
State/
territory
Years
Years
%
%
%
%
%
%

New South Wales
79.8
84.2
101.5
99.1
100.0
101.0
99.4
100.0
Victoria
80.3
84.4
101.7
99.1
100.6
101.1
99.5
100.2
Queensland
79.5
84.1
100.5
99.2
99.7
100.3
99.7
99.9
South Australia
79.7
84.0
100.6
99.2
100.0
100.3
99.6
100.0
Western Australia
80.1
84.6
101.4
98.9
100.4
101.5
99.6
100.5
Tasmania
78.3
82.5
99.2
97.9
98.3
98.3
98.1
98.3
Northern Territory
74.9
80.5
96.1
89.9
92.8
97.3
89.0
94.0
Australian Capital Territory
81.0
84.8
. .
. .
101.7
. .
. .
100.7
Australia(b)
79.7
84.2
. .
. .
100.0
. .
. .
100.0

. . not applicable
(a) Mortality differentials based on the relationships of 2009-2011 life expectancies at birth for each state/territory, capital city and balance of state compared to the Australian level.
(b) Includes Other Territories.



International comparison of projections

Australian life expectancy is currently amongst the highest in the world. According to the Population Reference Bureau (PRB) 2013 World Population Data Sheet, the combined life expectancy at birth of males and females globally is 70 years. Australian life expectancy (estimated by the PRB to be 82 years for both males and females combined) is above that for countries such as the United States of America (79 years)), Greece and New Zealand (both 81 years), and Canada (81 years). Australia's current life expectancy of 82 years is similar to that of Spain, Sweden, Iceland, and slightly lower than Japan and Switzerland (83 years).

The United Nations (2013) projects global life expectancy at birth to reach 75.9 years by 2045-2050, with Australian life expectancy continuing to rank amongst the highest in the world (87.2 years in 2045-2050). Combined life expectancy at birth in this set of ABS population projections is assumed to be 86.7 years in 2061 under the medium assumption (similar to the United Nations estimate) and 92.8 years under the high assumption.

Projected life expectancy at birth(a), United Nations

2005-2010
2025-2030
2055-2060
INCREASE 2005-2010 TO 2055-2060
Males
Females
Males
Females
Males
Females
Males
Females
years
years
years
years
years
years
years
years

Australia
79.4
83.9
82.3
86.8
86.1
90.7
6.7
6.8
Canada
78.2
82.8
81.3
85.5
84.8
89.0
6.6
6.2
China
73.2
75.8
76.2
78.8
79.8
82.4
6.6
6.6
France
77.3
84.3
80.5
87.4
84.4
91.3
7.1
7.0
Germany
77.1
82.3
80.5
85.1
84.3
88.9
7.2
6.6
Greece
77.3
82.3
80.7
85.0
84.3
88.6
7.0
6.3
Hong Kong (SAR of China)
79.4
85.4
82.8
88.8
87.0
93.1
7.6
7.7
India
63.3
66.7
67.7
71.5
72.4
76.5
9.1
9.8
Indonesia
67.6
71.6
71.4
75.8
76.8
80.5
9.2
8.9
Italy
78.7
84.1
81.8
87.2
85.9
91.2
7.2
7.1
Japan
79.2
86.0
82.3
89.2
86.2
93.0
7.0
7.0
Netherlands
78.0
82.2
81.1
84.7
84.5
88.1
6.5
5.9
New Zealand
78.2
82.2
81.4
84.8
85.1
88.5
6.9
6.3
Papua New Guinea
59.5
63.7
62.2
66.7
65.5
70.3
6.0
6.6
Spain
78.0
84.4
81.0
87.4
84.8
91.3
6.8
6.9
Sweden
79.0
83.1
81.7
85.8
85.3
89.3
6.3
6.2
United Kingdom
77.5
81.7
80.9
84.3
84.4
87.8
6.9
6.1
United States of America
75.6
80.6
79.0
83.1
82.7
86.5
7.1
5.9
Yemen
60.8
63.4
64.0
66.9
67.5
70.8
6.7
7.4
World
66.5
71.0
70.6
75.1
75.1
79.5
8.6
8.5

(a) Only once variant of future mortality trends (median path) was used for each country.
Source: United Nations, Department of Economic and Social Affairs, Population Division 2013, World Population Prospects: The 2012 Revision, Volume 1: Comprehensive Tables.


NET OVERSEAS MIGRATION

Summary

Three assumptions have been made about Australia's future levels of net overseas migration (NOM):
  • 280,000 people per year (high),
  • 240,000 people per year (medium); and
  • 200,000 people per year (low).

In addition, a zero net overseas migration assumption has been included to facilitate analysis of the effect of overseas migration on Australia's future population.

Assumptions of NOM in previous ABS population projections have been derived from an analysis of historical figures, taking into account information such as moving averages over time. For the first time, ABS projections have used the 'Outlook for Net Overseas Migration' forecast data produced by the Department of Immigration and Border Protection (DIBP) as an input into the NOM assumptions. DIBP is well placed to produce short term NOM assumptions, but beyond 2016-17 the ABS has placed more weight on established trends in NOM.

Trends

Annual levels of NOM have fluctuated considerably in Australia over the past 25 years. For financial years, the level has been as low as 30,000 in 1992-93 to a high of 300,000 in 2008-09. NOM has also been increasing as a percentage of overall population growth in Australia. In 2000 its proportion of total population growth was less than half (the other population growth element is natural increase - the net of births minus deaths). It is currently about 60% of total population growth.

Net overseas migration and natural increase, Australia (a)
Graph: Net overseas migration and natural increase, Australia (a)



Observed and assumed net overseas migration

Three assumptions have been made about Australia's future levels of NOM: 280,000 people per year (high), 240,000 people per year (medium) and 200,000 people per year (low). The high and low assumptions are phased in from the current level of NOM up to 2021, and all assumptions are held constant from 2021 onwards.

For the first five years of the projection period, where DIBP numbers will be used, the distance from the medium assumption and that of low or high assumptions will be 10,000 for 2012-13. After this, the gap will continue to increase until it reaches 40,000 by 2020-21 and will remain constant after that year.

Unlike births and deaths, NOM has fluctuated considerably over the years and the immigration component of NOM is not wholly set by the Federal Government at a set rate of the population (the emigration component has no controls placed upon it). Assumptions for NOM are therefore set at numeric levels rather than rates, in contrast to assumptions on fertility and mortality. NOM can be expected to continue to fluctuate in the future as demand for migrants will rise and fall and emigration patterns may change.

Net overseas migration, Observed and assumed

Low assumption
Medium assumption
High assumption
Year ending 30 June
no.
no.
no.

OBSERVED

2010
196 058
196 058
196 058
2011
180 372
180 372
180 372
2012
223 149
223 149
223 149

ASSUMED

2013
227 000
237 000
247 000
2014
228 000
242 000
256 000
2015
233 000
251 000
268 000
2016
230 000
251 000
272 000
2017
226 000
251 000
276 000
2018
219 000
248 000
277 000
2019
213 000
245 000
278 000
2020
206 000
243 000
279 000
2021-2101
200 000
240 000
280 000

Net overseas migration, Australia - Observed and assumed
Graph: Net overseas migration, Australia—Observed and assumed


In addition to the three main assumptions, a zero NOM scenario has been included. This is intended to facilitate analysis of population growth and provide an indication of the cumulative effect of varying levels of NOM over the projection period.

Assumed state/territory and capital city/balance of state share of net overseas migration

Each state and territory's proportion of NOM is based on an average of the last three years of NOM data. For all assumptions, NOM was allocated from 2013 as follows: New South Wales receives 27.6% of total NOM, Victoria 25.3%, Queensland 19.4%, South Australia 5.3%, Western Australia 19.7, Tasmania 0.6%, the Northern Territory 0.9% and the Australian Capital Territory 1.2%.

The table below shows the observed and assumed state/territory net overseas migration distribution:

Assumed net overseas migration, State/territory share

NSW
Vic.
Qld
SA
WA
Tas.
NT
ACT
Year ended 30 June
%
%
%
%
%
%
%
%

2013
26.2
24.1
19.8
5.2
21.8
0.5
1.1
1.3
2014
26.6
24.5
19.7
5.2
21.1
0.5
1.1
1.3
2015
27.0
24.9
19.6
5.2
20.4
0.5
1.1
1.3
2016-2061
27.6
25.3
19.4
5.3
19.7
0.6
0.9
1.2



As NOM data are not currently available below the state/territory level, an indirect method to calculate the capital city/balance of state (CC/BoS) levels of NOM is used. NOM at this level is derived from the 2006 and 2011 Census questions on place of usual residence one year ago and five years ago. The process behind the assumptions involves:
  • estimating CC/Bos shares of state/territory arrivals from Census data; that is, people resident overseas one year ago;
  • estimating CC/Bos overseas departures data from the Census-a synthesis of the one and five years ago Census data; that is, CC/Bos data for those residing in Australia five years previously and who were overseas residents one year ago, but then were Australian residents again on Census night;
      • scaling this CC/Bos Census departure data to state/territory passenger card departures data by Australian and non-Australian citizenship (this is done as the Census data is biased towards estimating departures of Australian citizens, who have different residence patterns at the CC/Bos level to non-Australian citizens. Scaling to state/territory citizenship structures ensures that the CC/Bos departures data more accurately reflects the relative proportions of overseas departures from capital cities and balances of state); and
      • proportions of arrivals and departures to each CC/Bos were applied to the state/territory NOM arrivals and departures assumptions. These share-of-state proportions were held constant for the entire projection period.

Similar 2006 and 2011 Census tabulations are used to calculate CC/Bos shares of state/territory age/sex overseas arrivals and departures. These are applied to state/territory age/sex NOM arrivals and departures assumptions then constrained to the CC/Bos total arrivals and departures described above.

Assumed net overseas migration, Capital city/balance of state - 2021 onwards

NSW
Vic.
Qld
SA
WA
Tas.
NT
ACT
Aust.(a)
no.
no.
no.
no.
no.
no.
no.
no.
no.

HIGH ASSUMPTION

Capital city
70 132
66 586
32 322
13 689
48 047
1 003
1 845
3 360
236 984
Balance of state
7 148
4 254
21 998
1 151
7 113
677
675
. .
43 016
Total
77 280
70 840
54 320
14 840
55 160
1 680
2 520
3 360
280 000

MEDIUM ASSUMPTION

Capital city
60 921
57 556
27 955
11 808
41 293
866
1 625
2 880
204 904
Balance of state
5 319
3 164
18 605
912
5 987
574
535
. .
35 096
Total
66 240
60 720
46 560
12 720
47 280
1 440
2 160
2 880
240 000

LOW ASSUMPTION

Capital city
51 710
48 524
23 588
9 927
34 539
730
1 406
2 400
172 824
Balance of state
3 490
2 076
15 212
673
4 861
470
394
. .
27 176
Total
55 200
50 600
38 800
10 600
39 400
1 200
1 800
2 400
200 000

. . not applicable
(a) Includes Other Territories.



Assumed age structure of net overseas migration

The assumed age/sex structure of NOM for the states and territories is derived from the 2010-2012 NOM. NOM arrivals and departures by state/territory, age and sex are simultaneously constrained to the total assumed NOM level for Australia and to the assumed state/territory shares of NOM. The assumed age/sex structures are held constant throughout the projection period.

For more information on the age structure of NOM, see Migration, Australia, 2010-11 (cat. no. 3412.0).


NET INTERSTATE MIGRATION

Summary

Interstate migration, as an unrestricted and unregulated effect on population, is volatile and an unpredictable component in population estimation or projection. The movement of people between the states and territories of Australia is influenced by many factors such as varying economic opportunities, overseas immigration and settlement patterns, lifestyle choices and marketing campaigns targeting interstate movers by state/territory governments. As the effect of these factors cannot be anticipated, past net interstate migration trends are used as the basis for assuming future levels.

Historical data

Net interstate migration estimates since 1994 are shown below. These are calculated using Medicare change of address records and Census data on usual residence one year ago and five years ago.

Net interstate migration - 1994-2012

NSW
Vic.
Qld
SA
WA
Tas.
NT
ACT
Year ending 30 June
'000
'000
'000
'000
'000
'000
'000
'000

1994
-12.2
-29.2
44.9
-4.0
3.8
-2.1
-0.9
-0.4
1995
-13.5
-22.0
40.2
-7.1
5.1
-2.7
0.4
-0.5
1996
-14.8
-12.8
32.6
-6.2
4.1
-2.6
0.3
-0.7
1997
-10.7
-6.2
19.6
-3.3
4.7
-3.3
1.8
-2.5
1998
-12.2
-0.3
17.4
-2.0
3.2
-3.6
-0.5
-2.0
1999
-13.1
2.5
16.7
-1.6
0.3
-3.3
-1.0
-0.5
2000
-14.3
5.2
18.5
-3.5
-2.2
-2.6
-0.9
-0.1
2001
-16.3
5.2
20.0
-2.4
-3.1
-2.1
-1.6
0.4
2002
-25.1
3.6
30.0
-1.3
-3.6
-1.4
-2.0
-0.2
2003
-32.5
-0.7
38.0
-1.2
-2.0
2.0
-2.8
-0.8
2004
-31.1
-3.1
35.5
-2.9
2.1
2.6
-1.5
-1.6
2005
-26.3
-3.1
30.4
-3.2
2.2
0.3
0.6
-0.8
2006
-25.6
-1.8
26.6
-2.7
3.9
-0.1
-0.6
0.3
2007
-26.3
-1.6
23.4
-3.4
5.4
-0.5
0.4
2.5
2008
-20.8
-1.9
19.4
-4.2
5.0
0.7
1.4
0.3
2009
-18.7
1.5
14.7
-4.4
5.0
1.1
0.9
-0.3
2010
-9.5
3.3
6.2
-2.7
2.1
0.7
-0.7
0.4
2011
-13.5
3.5
6.8
-2.6
7.0
-
-2.5
1.4
2012
-18.4
1.2
11.8
-2.4
11.1
-2.6
-1.5
0.7

- nil or rounded to zero (including null cells)


New South Wales and South Australia have continued to experience net interstate losses, not recording a net interstate migration gain in the last 40 and 21 years, respectively. Queensland continues to be the largest beneficiary of net interstate migration since 1972, with Western Australia also recording gains in net interstate migration. Western Australia's net gain has been recorded for the past 9 years but has increased significantly in the last two years.

Victoria, Tasmania, the Northern Territory and the Australian Capital Territory have seen fluctuations in their net interstate migration. Victoria has returned to net migration gains after recording six years of losses. After experiencing positive or stable net migration from 2008 to 2011, Tasmania has recorded a net migration loss in 2012, returning to the long term trend for the state. The Northern Territory has returned to net interstate migration losses after gains from 2007 to 2009. Since 2006, the Australian Capital Territory has recorded gains except in 2009.

State/territory and capital city/balance of state assumptions

Levels of assumed net interstate migration were derived by analysing trends over the past 5 years and constraining them such that they sum to zero. The assumptions reflect the view that each State/Territory will trend towards their short term average. Three assumptions have been made about future net interstate migration levels:

Three assumptions have been made about future net interstate migration levels:
  • large interstate flows: relatively large net interstate migration gains for some states and territories, corresponding to relatively large losses for other states and territories. For example, this equates to large net gains in Queensland and correspondingly large net losses in New South Wales and South Australia;
  • medium interstate flows: medium net interstate migration gains for some states and territories, and medium losses for others; and
  • small interstate flows: relatively small net interstate migration gains for some states and territories, and small losses for others.

The medium series assumptions are based on NIM averages for the states and territories in the period 2007-2012. The high and low assumptions were based on the minimum and maximum values of NIM. Adjustments were made to ensure that each State maintains the direction of interstate migration (established by trends), and that the overall NIM is zero.

It should be noted that for some states the large interstate flows assumption corresponds to large net interstate migration losses, therefore the small interstate flows assumption will yield greater population growth in such cases.

Net interstate migration assumptions for the states and territories are as follows:

ASSUMED NET INTERSTATE MIGRATION, 2013-2061

NSW
Vic.
Qld
SA
WA
Tas.
NT
ACT
Year ended 30 June
'000
'000
'000
'000
'000
'000
'000
'000

LARGE INTERSTATE FLOWS ASSUMPTION(a)

2013
-22.0
2.0
14.0
-3.0
11.0
-1.5
-1.5
1.0
2014
-25.5
3.0
16.0
-3.5
10.5
-
-2.0
1.5
2015-2061
-29.0
4.0
18.0
-4.0
10.0
1.0
-2.0
2.0

MEDIUM INTERSTATE FLOWS ASSUMPTION

2013
-18.0
1.5
12.0
-2.5
9.5
-1.5
-1.5
0.5
2014
-17.5
2.0
12.0
-3.0
7.5
-1.0
-1.0
1.0
2015-2061
-17.0
2.0
12.0
-3.0
6.0
-
-1.0
1.0

SMALL INTERSTATE FLOWS ASSUMPTION(a)

2013
-14.0
1.0
10.0
-2.5
8.0
-2.0
-1.0
0.5
2014
-9.5
0.5
8.0
-2.0
5.0
-1.5
-0.5
-
2015-2061
-5.0
-
6.0
-2.0
2.0
-1.0
-
-

- nil or rounded to zero (including null cells)
(a) The large interstate flows assumption corresponds to large net interstate losses for New South Wales, South Australia and the Northern Territory, where the small interstate flows assumption yields the greater population growth.


Internal migration assumptions for capital cities and balance of states were based on indirectly estimated historical trends of net internal migration. Net total migration (overseas and internal) for each capital city/balance of state was assumed to be the difference between population growth and natural increase for these regions. Net internal migration was then assumed to be the difference between net total migration and the synthetic NOM estimates for capital city and balance of state (for the derivation of these NOM estimates see the Net Overseas Migration section of Chapter 2: Assumptions).

Net internal migration, Capital cities - Observed and assumed

Sydney
Melbourne
Brisbane
Adelaide
Perth
Hobart
Darwin
Year ended 30 June
'000
'000
'000
'000
'000
'000
'000

OBSERVED

2002
-42.9
-1.3
13.5
-1.1
-1.0
-0.6
-1.0
2003
-44.5
-4.0
15.7
-1.5
0.9
0.8
-1.6
2004
-28.5
-3.6
13.2
-3.0
5.1
0.9
-0.9
2005
-39.7
-4.2
9.6
-3.2
0.8
0.1
0.8
2006
-35.2
-4.7
6.7
-2.6
2.9
-0.1
-0.1
2007
-32.4
-4.3
5.5
-3.9
9.6
-0.4
0.7
2008
-29.2
-5.7
3.1
-4.4
3.7
0.2
1.2
2009
-29.7
-3.9
2.5
-4.0
3.2
0.3
0.8
2010
-26.2
-5.4
-
-3.0
1.3
0.5
-0.2
2011
-28.4
-5.5
1.4
-2.3
5.9
0.2
-1.2
2012
-26.1
-3.7
0.4
-2.8
8.9
-0.9
-0.6

LARGE INTERSTATE FLOWS ASSUMPTION(a)

2013
-20.2
-1.7
1.1
-2.5
8.9
-1.3
-1.0
2014
-13.0
-1.1
0.8
-2.0
5.6
-0.9
-0.5
2015-2061
-6.7
-
0.5
-1.9
2.2
-0.5
-

MEDIUM INTERSTATE FLOWS ASSUMPTION

2013
-25.9
-2.6
1.4
-2.5
10.5
-1.0
-1.4
2014
-24.0
-4.2
1.2
-3.0
8.4
-0.6
-1.1
2015-2061
-22.7
-4.0
1.1
-2.9
6.5
-
-1.2

SMALL INTERSTATE FLOWS ASSUMPTION(a)

2013
-31.7
-2.7
1.6
-3.0
12.2
-1.0
-1.4
2014
-35.0
-5.1
1.7
-3.5
11.7
-
-2.1
2015-2061
-38.7
-6.4
1.6
-3.9
10.9
0.5
-2.4

- nil or rounded to zero (including null cells)
(a) The large interstate flows assumption corresponds to large net interstate losses for New South Wales, South Australia and the Northern Territory, where the small interstate flows assumption yields the greater population growth.

Net internal migration, Balance of state - observed and assumed

Balance of NSW
Balance of Vic.
Balance of Qld
Balance of SA
Balance of Wa
Balance of Tas.
Balance of NT
Year ended 30 June
'000
'000
'000
'000
'000
'000
'000

OBSERVED

2002
17.8
4.9
16.5
-0.2
-2.5
-0.8
-1.0
2003
12.1
3.2
22.3
0.3
-2.9
1.2
-1.2
2004
-2.6
0.5
22.3
-
-3.0
1.6
-0.6
2005
13.4
1.2
20.8
-0.1
1.5
0.2
-0.2
2006
9.6
2.9
19.9
-0.1
1.1
-
-0.4
2007
6.1
2.7
17.8
0.5
-4.3
-0.2
-0.3
2008
8.4
3.7
16.3
0.2
1.2
0.5
0.2
2009
11.1
5.5
12.2
-0.4
1.8
0.7
0.1
2010
16.7
8.7
6.2
0.3
0.8
0.1
-0.4
2011
14.9
9.0
5.4
-0.3
1.1
-0.3
-1.3
2012
7.7
4.9
11.4
0.5
2.2
-1.6
-0.9

LARGE INTERSTATE FLOWS ASSUMPTION(a)

2013
6.2
2.7
8.9
-
-0.9
-0.7
-
2014
3.5
1.6
7.2
-
-0.6
-0.6
-
2015-2061
1.7
-
5.5
-0.1
-0.2
-0.5
-

MEDIUM INTERSTATE FLOWS ASSUMPTION

2013
7.9
4.1
10.6
-
-1.0
-0.5
-0.1
2014
6.5
6.2
10.8
-
-0.9
-0.4
0.1
2015-2061
5.7
6.0
10.9
-0.1
-0.5
-
0.2

SMALL INTERSTATE FLOWS ASSUMPTION(a)

2013
9.7
4.7
12.4
-
-1.2
-0.5
-0.1
2014
9.5
8.1
14.3
-
-1.2
-
0.1
2015-2061
9.7
10.4
16.4
-0.1
-0.9
0.5
0.4

- nil or rounded to zero (including null cells)
(a) The large interstate flows assumption corresponds to large net interstate losses for New South Wales, South Australia and the Northern Territory, where the small interstate flows assumption yields the greater population growth.


Age/sex structure of interstate migration

All assumptions are separated into arrivals and departures for each state/territory and capital city/balance of state. Rates for arrivals and departures for the states and territories are generated from movement data from recent Censuses to obtain age/sex levels. Further, 2006 and 2011 Census data are used to generate age/sex arrival and departure levels for each capital city/balance of state. As a result, all age/sex arrival and departure disaggregations sum to the net internal migration assumptions.