Estimates and projections, Australian Aboriginal and Torres Strait Islander population

The ABS used the cohort-component method for producing population projections for the period 2022 to 2031 based on the 2021 Census of Population and Housing. In this method, assumptions made about future levels of fertility, mortality, overseas migration and internal migration are applied to the 2021 Census base population (applied 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.

Because the identification of Aboriginal and/or Torres Strait Islander people changes significantly between Censuses, a similar method was used to produce population backcast estimates which span the period 2011 to 2020. This technique requires assumptions to be made about past levels of mortality taking into account the most recent 2021 Census data to utilise the best quality estimates available. These are applied to the 2021 base population to obtain a 'reverse-survived' population for the previous year. The assumptions are then applied to this new reverse-survived population to obtain a population for the preceding year. This process is repeated until the first year of the estimation period is reached. Combined with the projections this produces a population times series from 2011 to 2031 for the population identified in the 2021 Census.

Estimates and projections presented in this release supersede estimates and projections based on earlier censuses. The assumptions used differ from those in previous publications. As a result, and in addition to the use of a different base population, which is significantly larger than the previous base population, the size, structure and components of the estimated and projected Aboriginal and Torres Strait Islander population are different to those previously published for the same period.

• Backcast estimates of the Aboriginal and Torres Strait Islander population in this release span the period 30 June 2011 to 30 June 2020 and are available for Australia, the States and Territories and Remoteness Areas.
• Projections of the Aboriginal and Torres Strait Islander population in this release span the period 30 June 2022 to 30 June 2031 and are available for Australia, States and Territories, Indigenous Regions and Remoteness Areas.

The base population is the Aboriginal and Torres Strait Islander estimated resident population of Australia at 30 June 2021, derived from 2021 Census counts of the Australian Aboriginal and Torres Strait Islander population, adjusted for net undercount as measured by the Post Enumeration Survey (PES). All estimates therefore reflect the identification of the population at the time of the 2021 Census.

A single time series of Aboriginal and Torres Strait Islander backcast estimates for the period 2011 to 2021 has been produced.

Over this period, life expectancy at birth is assumed to be:

• constant between 2016 to 2021 at the 2020-2022 level. This is 71.9 years for males and 75.6 years for females at the national level.
• constant between 2011 to 2016 at the revised 2015-2017 level. This is 71.5 years for males and 75.4 years for females at the national level.

Net interstate migration for each of the above 2 intercensal periods was based on levels observed in each respective intercensal period.

Zero net overseas migration occurred across the entire series with no arrivals and departures.

Assumptions have been formulated on the basis of past demographic trends, in conjunction with consultation with various experts and government department representative at the national and state/territory level. They do not attempt to allow for non-demographic factors (such as major government policy decisions, economic factors, natural disasters, epidemic or significant health treatment improvements) which may alter future demographic behaviour or outcomes. They also assume no identification change over this period.

Additional assumptions regarding the remaining demographic factors for the projections are:

• constant levels of net interstate migration using the average of the 2016 and 2021 Census years
• zero net overseas migration with no arrivals and no departures
• zero unexplained growth in Aboriginal and Torres Strait Islander population.

By considering the above assumptions, 9 projection series were produced. Three main series have been selected from these to provide a range of projections for analysis and discussion in this publication. These series are referred to as high, medium and low.

Sensitivity analysis was undertaken around the medium main projection series. The remaining 6 alternative series show the sensitivity of the fertility, paternity and mortality assumptions.

The 3 main series respectively imply a high, medium and low overall growth rate of the Aboriginal and Torres Strait Islander population. It is expected that the medium series will be the most appropriate choice for most users. The ABS will be using the medium series in calculating fertility and mortality rates for inclusion in its annual Births and Deaths publications.

The effect of alternative assumptions on the size of the future Aboriginal and Torres Strait Islander population is described in Sensitivity to Projection Assumptions.

The population projections are not intended as forecasts or predictions but are illustrations of growth and change in the population that would occur if assumptions made about future demographic trends were to prevail over the projection period. 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 acknowledges a range of the possible future size, distribution and age structure of Australia's Aboriginal and Torres Strait Islander population.

There is also some level of uncertainty surrounding 2021 Aboriginal and Torres Strait Islander Census counts and population estimates on which the projections are based, as well as data quality issues relating to registered births and deaths of Aboriginal and Torres Strait Islander people. Information on data quality issues related to Aboriginal and Torres Strait Islander estimates and projections are available in the Quality Declaration.

The ABS Births collection identifies a birth as being an Aboriginal and/or Torres Strait Islander person where either parent identifies as being of Aboriginal and/or Torres Strait Islander origin on the birth registration form.

Therefore, Aboriginal and Torres Strait Islander births may be attributed to Aboriginal and Torres Strait Islander:

• mothers, irrespective of whether or not the father identified as being of Aboriginal and/or Torres Strait Islander origin
• fathers, irrespective of whether or not the mother identified as being of Aboriginal and/or Torres Strait Islander origin.

For simplicity, birth rates of Aboriginal and Torres Strait Islander mothers are referred to in this release as fertility rates, while birth rates where the father is of Aboriginal and Torres Strait Islander origin and the mother's Indigenous status is non-Indigenous or not stated are referred to as paternity rates.

To produce population projections using the cohort-component method, assumptions for each year of the projection period are required for age-specific fertility rates, age-specific paternity rates and the Aboriginal and Torres Strait Islander sex ratio at birth.

Of the 24,388 Aboriginal and Torres Strait Islander births registered in 2022:

• 23% were births for which both parents were identified as being of Aboriginal and Torres Strait Islander origin on the birth certificate
• 45% were births where only the mother was of Aboriginal and Torres Strait Islander origin (including births where paternity was not acknowledged or the father's Indigenous status was not stated)
• 32% were births where only the father was of Aboriginal and Torres Strait Islander origin (including births where the mother's Indigenous status was not stated).
   

The proportion of Aboriginal and Torres Strait Islander births attributed to Aboriginal and Torres Strait Islander mothers and/or Aboriginal and Torres Strait Islander fathers differs considerably between the states and territories.

In 2022:

• Western Australia had the highest proportion of births (42%) where both the mother and father were of Aboriginal and/or Torres Strait Islander origin
• Victoria had the lowest proportion of births (10%) where both mother and father were of Aboriginal and/or Torres Strait Islander origin
• 42% of births in Tasmania were to non-Indigenous mothers and Aboriginal and/or Torres Strait Islander fathers (11% in the Northern Territory).
   

Population projections require an assumed sex ratio at birth in order to split total projected births into male and female births. The sex ratio for Aboriginal and Torres Strait Islander births registered in Australia during 2018-2022 fluctuates around 102 to 107 male births per 100 female births. A constant ratio of 105 males per 100 female births has been assumed for the duration of the projection period.

Three main assumptions have been made for future fertility rates of Aboriginal and Torres Strait Islander women:

• constant fertility rates at the 2021 level
• an annual decline of 1.2% in fertility rates
• an annual decline of 1.5% in fertility rates. 

These assumptions were primarily chosen on the basis of the declining trend in fertility as indicated by data from the 'children ever born' question asked across successive Censuses.

The same rate of decline in fertility rates have been assumed for each state and territory, Indigenous Region and Remoteness Area.

Cohort fertility rates, based on the 'children ever born' question asked in the Census illustrate a decline in Aboriginal and Torres Strait Islander fertility over time.

The number of children ever born provides information on actual fertility outcomes of women of different ages. In particular, the number of children ever born to women aged 40 to 44 years can be regarded as a measure of completed fertility; that is, on average how many children this group of women each had throughout their entire reproductive lifetimes.

Aboriginal and Torres Strait Islander women aged 40 to 44 years had on average:

• 3.97 babies per woman in the 1986 Census
• 3.10 babies per woman in the 1996 Census
• 2.84 babies per woman in the 2006 Census
• 2.82 babies per woman in the 2011 Census
• 2.77 babies per woman in the 2016 Census
• 2.68 babies per woman in the 2021 Census. 

The average number of children ever born to Aboriginal and Torres Strait Islander women has been declining for each age group for more than 3 decades. These declines, particularly in the younger age groups, indicate probable declines in the future overall level of Aboriginal and Torres Strait Islander fertility.

The total fertility rate (TFR), based on birth registrations, 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 (ages 15 to 49 years).

The TFR for Aboriginal and Torres Strait Islander women:

• was 1.86 babies per woman in 2006, increasing to 2.35 in 2010
• decreasing over the period 2011 to 2014 before increasing to 2.37 babies per woman by 2018
• then decreasing once again over the period 2019 and 2020 before increasing to 2.35 babies per woman in 2022.
   

In summary, while fertility rates based on birth registrations of Aboriginal and Torres Strait Islander children may provide some evidence for assuming constant or increasing Aboriginal and Torres Strait Islander fertility, cohort fertility rates based on the 'children ever born' question asked in the Census indicate long-term declines. Assumptions that take both sets of evidence into account have been made but with more emphasis given to the 'children ever born' data.

• High series: assumes constant fertility rate as observed on 30 June 2021.
• Medium series: assumes an annual decline of -1.2%. This is based on trend in 2011-2021 in the total population TFR using the respective Census years’ ERP.
• Low series: assumes an annual decline of -1.5%. This is a faster decline than the trend in 2011-2021 in the total population TFR based on the respective Census years’ ERP.

Assumed age-specific fertility rates for Aboriginal and Torres Strait Islander women are based on 3 years of birth registrations (2020-2022) in order to minimise the effect of year-to-year fluctuations in registrations.

As rates are required on a financial year basis they were adjusted to account for the 6-month period between the mid-point of the period 2020 to 2022 (calendar year fertility rates) and 2021 to 2022 (financial year fertility rates).

Assumed declines in fertility rates are applied uniformly across relevant age groups.

The projections in this release apply fertility assumptions for sub-state geographies by aggregating Indigenous Regions (IREGs) into 2 groups for each state and territory (except Tasmania and the Australian Capital Territory):

• Capital city IREG (for example, Adelaide IREG)
• Rest of state/territory IREGs combined (for example, Port Augusta IREG and Port Lincoln - Ceduna IREG combined).
   

Assumed fertility rates for Remoteness Areas were calculated using the same technique as for the states and territories.

The total paternity rate (TPR) is defined as the average number of Aboriginal and Torres Strait Islander babies born per Aboriginal and/or Torres Strait Islander father where the mother's Indigenous status is non-Indigenous or not stated, and is calculated in the same way as the TFR.

Three main assumptions have been made for future paternity rates:

• an annual increase of 0.5%
• constant paternity rates
• an annual decrease of 0.5%.

Constant paternity rates have been assumed for each state and territory, Indigenous Region, and Remoteness Area.

As with the TFR, the time series of the TPR is based on population estimates which are not strictly comparable over time. Based on birth registrations, the TPR remained constant at 1.03 births per Aboriginal and/or Torres Strait Islander male between 2011 and 2022.

The 'children ever born' question is not asked of males in the Census. Therefore, there is no reliable source other than birth registrations for calculating paternity rate.

• High series: assumes an annual increase in paternity rate of 0.5%.
• Medium series: assumes constant paternity rate over the projection period.
• Low series: assumes an annual decrease of 0.5% in paternity rate.

Assumed age-specific paternity rates for Aboriginal and Torres Strait Islander men are based on 3 years of birth registrations (2020-2022) where the mother's Indigenous status is non-Indigenous or not stated. Assumed constant paternity rates are applied uniformly across relevant age groups.

Assumed paternity rates for IREGs were calculated using the same technique as for the states and territories.

Assumed paternity rates for Remoteness Areas were calculated using the same technique as for the states and territories.

To produce population projections using the cohort-component method, life tables are required for each year of the projection period. These are calculated in 2 steps:

• life expectancy at birth for each projection year is assumed
• life tables, based on the 2020-2022 age/sex structure of mortality, are generated to match the assumed life expectancies at birth. 

Survivorship ratios from the life tables are then applied to the population by single year of age and sex.

Assumptions for mortality at lower geographical levels are based on 2020-2022 differentials between Australia and each state or territory, groups of Indigenous Regions, and Remoteness Areas.

At the national level, Aboriginal and Torres Strait Islander life expectancy at birth for the period 2020-2022 is estimated to be 71.9 years for males and 75.6 years for females (see Aboriginal and Torres Strait Islander life expectancy, 2020-2022).

As survivorship ratios are needed on a financial year basis, it is necessary to adjust life expectancy at birth estimates to account for the 6-month period between the midpoint of 2020-2022 (calendar year life expectancy) and 2020-2021 (financial year life expectancy). However, this adjustment was not required this time as constant mortality assumption at the 2020-2022 level was used for producing backcast estimates. This means that midpoint of calendar year life expectancy was the same as financial year life expectancy.

The ABS has compiled life tables for Aboriginal and Torres Strait Islander peoples after each Census since 1996. Due to changes in the methods and identification over time, 2020-2022 estimates of life expectancy at birth are not comparable to estimates for earlier periods. Assumptions about future levels of Aboriginal and Torres Strait Islander life expectancy at birth have therefore only be based on observed trends over the 2 most recent intercensal periods.

A study (Wilson, Condon and Barnes, 2007) found evidence that in the Northern Territory:

• life expectancy at birth increased from 52 years for males and 54 years for females in the 1960's, to 60 years and 68 years respectively in recent years
• improvements in infant mortality contributed to increases in life expectancy at birth between the late 1960's and early 1980's.
• Since then, life expectancy gains have been largely the result of improving mortality of people aged 45 years and over.

In addition, alternative measures indicate some improvement in mortality of Aboriginal and Torres Strait Islander peoples between 1991 and 2005. This includes declines in:

• mortality as measured by age-standardised death rates have been recorded in Western Australia and for females in the Northern Territory
• infant mortality have been recorded in Western Australia, South Australia and the Northern Territory.

For more information see The Health and Welfare of Australia's Aboriginal and Torres Strait Islander Peoples, Oct 2010, cat. no. 4704.0, Wang Z and Li SQ, 2010, Mortality in the Northern Territory 1967-2006, Health Gains Planning Information Sheet, Dec 2010, Northern Territory Government, Casuarina NT and SCRGSP (Steering Committee for the Review of Government Service Provision) 2011, Overcoming Indigenous Disadvantage: Key Indicators 2011, Productivity Commission, Canberra. 

Three life expectancy at birth assumptions have been used to produce the 3 main series.

Aboriginal and Torres Strait Islander life expectancy at birth differs between the states and territories. For the purposes of these projections, mortality differentials between each state/territory and Australia are calculated and applied to the assumed Australian life expectancies at birth to obtain assumed life expectancy at birth for the states and territories. This method assumes that the mortality differentials, based on those observed during 2020-2022, will remain constant throughout the projection period.

Due to small numbers of deaths registered as an Aboriginal and/or Torres Strait Islander death it was not possible to produce Aboriginal and Torres Strait Islander life tables for Victoria, South Australia, Tasmania and the Australian Capital Territory. For the purposes of the projections it is assumed that life expectancy at birth for:

• Victoria and Tasmania is the same as that for New South Wales
• South Australia is the same as that for Western Australia
• The Australian Capital Territory is the same as that derived for the Sydney Indigenous Region.
   

To apply assumptions on life expectancy at birth for alternative geographies, Indigenous Regions (IREGs) were aggregated into 2 groups for each state and territory (except Tasmania and the Australian Capital Territory):

• Capital city IREG (for example, Adelaide IREG)
• Rest of state/territory IREGs combined (for example, Port Augusta IREG and Port Lincoln - Ceduna IREG combined). 

To account for under-identification of deaths of Aboriginal and Torres Strait Islander people at smaller geographic level, the number of registered deaths of Aboriginal and Torres Islander people for each IREG group in 2020-2022 was adjusted using state and territory adjustment factors from the 2021 to 2022 Census and deaths linked data. For more information about the derivation and use of adjustment factors in the compilation of Aboriginal and Torres Strait Islander life tables for the states and territories, see Aboriginal and Torres Strait Islander life expectancy, 2020–2022. 

A life table methodology was used to obtain life expectancy at birth for 2020-2022 for each IREG group using adjusted deaths in conjunction with the 2021 Aboriginal and Torres Strait Islander population for each IREG group. Differentials were calculated as the ratio of Aboriginal and Torres Strait Islander life expectancy at birth for each IREG group. This method assumes that under-identification of Aboriginal and Torres Strait Islander deaths is consistent across all regions within each state and territory as information on under-identification is not available at IREG level. Mortality differentials are assumed to remain constant throughout the projection period. 

As noted above, Aboriginal and Torres Strait Islander life tables were not produced for Victoria, South Australia, Tasmania and the Australian Capital Territory. The following differentials have been used for IREG groups in these states and territories:

• Victoria: Melbourne IREG uses the Sydney IREG differential, the rest of Victoria IREG uses the rest of New South Wales IREG group differential
• South Australia: Adelaide IREG uses the Perth IREG differential, and the rest of South Australia IREG group uses the rest of Western Australia IREG group differential
• Tasmania uses the New South Wales state differential
• The Australia Capital Territory uses the Sydney IREG differential.

Aboriginal and Torres Strait Islander life expectancy at birth differentials for Remoteness Areas were calculated using the same method as that used for IREG groups. 

One assumption has been made for future net internal migration of Aboriginal and Torres Strait Islander people:

• constant levels of net interstate migration using the average of the 2016 and 2021 Census years based on address 5 years ago.

The 'place of usual residence five years ago' Census questions shows that the number of Aboriginal and Torres Strait Islander people who changed their state or territory of usual residence between:

• 2016 and 2021 was 31,970
• 2011 and 2016 was 25,960.

This measure was unable to account for:

• Aboriginal and Torres Strait Islander children under 5 years of age on Census night
• people whose place of residence 5 years ago was overseas
• people whose state or territory of usual residence 5 years ago was not recorded. 

In addition, Aboriginal and Torres Strait Islander people overseas on Census night were not counted in the Census. 

One assumption has been made for future net internal migration of Aboriginal and Torres Strait Islander people:

• in acknowledgement of the impacts on population movement due to the response to COVID-19 pandemic in 2020-2021, constant levels of net interstate migration using the average of 2016 and 2021 Census years based on address 5 years ago.

These figures are affected by a number of data quality issues, including Census net undercount and records for which Indigenous status was not stated. To account for these, net interstate migration estimates were adjusted by a proportion calculated by dividing Aboriginal and Torres Strait Islander ERP by Aboriginal and Torres Strait Islander Census counts, for each state and territory.

The adjusted net interstate migration estimates were then divided by 5 to obtain annual movements, which were assumed to remain constant over the projection period. In addition, they were used as constraints on migration assumptions for Indigenous Regions and Remoteness Areas.

The age/sex profile of intestate migration was derived from the 'place of usual residence one year ago' question from the 2021 Census. Arrival and departure rates for the states and territories were calculated by single year of age and sex and adjustments were made where appropriate to ensure the age/sex profiles of projected populations were plausible. To be consistent with the method of calculating net interstate migration, the average of the 2016 and 2021 arrivals and departures rates was used for the whole projection period. All age/sex arrival and departure disaggregations were constrained by the net internal migration assumption at the state/territory level.

Annual net migration estimates for each IREG were calculated in the same way as for the states and territories and were assumed to remain constant over the 10-year projection period.

Annual net migration estimates for each Remoteness Area were calculated in the same way as for states and territories, and were assumed to remain constant over the 10-year projection period. 

One assumption has been made for future net overseas migration of Aboriginal and Torres Strait Islander people:

• zero overseas migration, with zero arrivals and zero departures.

According to the 2021 Census there were 2,858 Aboriginal and Torres Strait Islander people resident in Australia in 2021 who lived overseas in 2016. Slightly fewer numbers of Aboriginal and Torres Strait Islander people resident in 2016 also lived overseas in 2011 (1,969 people).

This level of in-migration has a negligible effect on the size of the future Aboriginal and Torres Strait Islander population. In addition, there will also be some level of out-migration leading to an even smaller net migration rate.

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

On 25 March 2025, an additional projection series was added that includes an unexplained growth assumption. This is based on identification change between the 2016 and 2021 Censuses. For more information see Identification change series.

Zero unexplained growth has been assumed for all other projection series.

Sensitivity analysis was undertaken into the effect of fertility assumptions on the size of the future Aboriginal and Torres Strait Islander population and the number of projected births. The below table shows the projected Aboriginal and Torres Strait population and births in 2031 under 3 fertility assumptions:

Assuming fertility rates remain constant (high series) it is projected that:

• Aboriginal and Torres Strait Islander population of Australia will reach 1,188,900 people in 2031 (up from 1,179,100 in the medium series in 2031)
• births will be higher than in the medium series in 2031 (28,870 compared with 26,840)
• this will result in more Aboriginal and Torres Strait Islander children aged 0 to 14 years in 2031 than in the medium series (366,400 compared with 356,600). 

Based on the medium fertility assumption series (1.2% annual decline in fertility rates):

• Aboriginal and Torres Strait Islander population of Australia is projected to reach 1,179,100 people in 2031 (up from 983,700 in the medium series in 2021)
• births are projected to increase from 23,540 in 2022 to 26,840 in 2031. 

Assuming a 1.5% annual decline in fertility rates (low series):

• Aboriginal and Torres Strait Islander population of Australia is projected to reach 1,176,700 people in 2031 (down from 1,179,100 people in the medium series in 2031)
• births will be lower than in the medium series in 2031 (26,360 compared with 26,840)
• this will result in fewer Aboriginal and Torres Strait Islander children aged 0 to 14 years in 2031 than in the medium series (354,300 compared with 356,600).

Sensitivity analysis was undertaken into the effect of paternity assumptions on the size of the future Aboriginal and Torres Strait Islander population and the number of projected births.

The below table shows the projected Aboriginal and Torres Strait population and births in 2031 under the 3 paternity assumptions:

Assuming a 0.5% annual increase in paternity rates (high series):

• Aboriginal and Torres Strait Islander population of Australia is projected to reach 1,181,100 people in 2031 (up from 1,179,100 people in the medium series in 2031)
• births will be higher than in the medium series in 2031 (27,260 births compared with 26,840)
• This will result in more Aboriginal and Torres Strait Islander children aged 0 to 14 years in 2031 than in the medium series (358,600 compared with 356,600).

Based on the medium series paternity assumption (paternity rates remain constant):

• Aboriginal and Torres Strait Islander population of Australia is projected to reach 1,179,100 people in 2031 (up from 983,700 in 2021)
• births are projected to increase from 23,540 in 2022 to 26,840 in 2031.

Assuming a 0.5% annual decrease in paternity rates (low series) it is projected that:

• Aboriginal and Torres Strait Islander population of Australia will reach 1,177,200 people in 2031 (down from 1,179,100 in the medium series in 2031)
• births will be lower than in the medium series in 2031 (26,430 births compared with 26,840)
• This will result in fewer Aboriginal and Torres Strait Islander children aged 0 to 14 years in 2031 than in the medium series (354,700 compared with 356,600).

Sensitivity analysis was undertaken into the effect of life expectancy at birth assumptions on the size of the future Aboriginal and Torres Strait Islander population and the number of projected deaths.

The below table shows the projected Aboriginal and Torres Strait population and deaths in 2031 under the 3 life expectancy at birth assumptions:

Assuming an annual increase of 0.29 years for males and 0.20 years for females (high series):

• Aboriginal and Torres Strait Islander population of Australia is projected to reach 1,181,900 people in 2031 (up from 1,179,100 in the medium series in 2031)
• deaths are projected to be lower than in the medium series in 2031 (5,920 deaths compared with 6,430).

Based on the medium life expectancy assumption series (annual increase of 0.15 years for males and 0.10 years for females):

• Aboriginal and Torres Strait Islander population of Australia is projected to reach 1,179,100 people in 2031 (up from 983,700 in 2021)
• deaths are projected to increase from 5,070 in 2022 to 6,430 in 2031. 

Assuming life expectancy to remain constant for males and females (low series) it is projected that:

• Aboriginal and Torres Strait Islander population of Australia will reach 1,176,000 people in 2031 (down from 1,179,100 in the medium series in 2031)
• deaths are projected to be higher than in the medium series in 2031 (7,000 deaths compared with 6,430).

The Aboriginal and Torres Strait Islander population has a relatively young age structure with a median age of 24.0 years in 2021 (38.9 years for the non-Indigenous population).

• in 2011 the median age was 22.0 years
• by 2031 the median age is projected to be between 25.4 and 25.7 years.

The Aboriginal and Torres Strait Islander population is projected to increase across all age groups between 2021 and 2031.

In 2021, the number of children aged 0 to 14 years was 325,800. This is projected to:

• increase to between 352,200 and 368,500 children in 2031
• decrease as a proportion of the population, from 33.1% in 2021 to between 30.1% and 30.9% in 2031.

The number of people aged 15 to 64 years was 604,500 in 2021. This is projected to:

• increase to between 731,900 and 734,200 people in 2031
• increase as a proportion of the population, from 61.5% in 2021 to between 61.5% and 62.5% in 2031.

In 2021, the number of people aged 65 years and over was 53,300. This is projected to:

• increase to between 87,600 and 90,900 people in 2031
• increase as a proportion of the population, from 5.4% in 2021 to between 7.5% and 7.6% in 2031.

All 3 series project continuing population growth in the majority of Indigenous Regions between 2021 and 2031.

Of all Indigenous Regions, the Aboriginal and Torres Strait Islander population is projected to be the fastest growing in:

• Perth, Western Australia (between 2.7% and 2.8%)
• Brisbane, Queensland (between 2.6% and 2.8%)
• Townsville - Mackay, Queensland (between 2.5% and 2.7%). 

Katherine and Tennant Creek, in the Northern Territory, are the only Indigenous Regions where the Aboriginal and Torres Strait Islander population is projected to decrease between 2021 and 2031. This can be attributed to assumed net migration loss.