Identification as an Aboriginal and/or Torres Strait Islander person in the Census over time, 2011 to 2021

Counts of people who identified as being of Aboriginal and/or Torres Strait Islander origin in the Census inform statistics such as Australia’s official population estimates and statistical indicators, such as those used in Closing the Gap reporting. Understanding changes in counts of people reporting to be of Aboriginal and/or Torres Strait Islander origin is important when analysing and interpreting Census data.

The count of Aboriginal and Torres Strait Islander people in the Census has been growing. In 2021, more than half of this increase was due to non-demographic changes, or changes that aren’t due to births, deaths, or migration, such as an increase in the number of people who identified as an Aboriginal and/or Torres Strait Islander person in the Census. A person’s decision to identify as an Aboriginal and/or Torres Strait Islander person can be informed by many personal and external influences, both historical and contemporary.

Understanding change in counts of Aboriginal and Torres Strait Islander Australians: Census, 2021 looked at change in counts for groups of people, for example, people living in New South Wales, between Censuses. This article uses the Australian Census Longitudinal Dataset to look at how a sample of individuals in the Census reported their Indigenous status over time. The changes in identification described in this article are similar to what was reported previously in analysis of the 2006, 2011 and 2016 Censuses in the ACLD.

The Australian Census Longitudinal Dataset (ACLD) can be used to measure changes in how Australia responds to questions in the Census over time. This article focuses on changes in how people in the ACLD reported their Aboriginal and/or Torres Strait Islander status in the Census between 2011 and 2021.

The 2011-2016-2021 ACLD is a representative sample of around 5% of records (1.2 million) from the 2011 Census, brought together with corresponding records from the 2016 and 2021 Censuses. The total number of records from the original 2011 sample that were successfully linked to both 2016 and 2021 Census records was 814,337. Of these linked records, 22,586 belonged to people who identified as an Aboriginal and/or Torres Strait Islander person in one or more of these Censuses.

People who were included in the 2011 Census sample but whose 2016 and/or 2021 response could not be linked are excluded from this analysis. Some reasons why a record might not link include:

• 2016 and/or 2021 Census information for the person was incomplete
• a person was not counted in the 2016 and/or 2021 Census
• a person died prior to the 2016 or 2021 Census.

A weighted population is used in this article for analysis. Weighting is used to adjust a sample so that the information can be used to represent the relevant population. To do this, a 'weight' is allocated to each sample unit - in this case, persons. The weight can be considered an indication of how many people in the relevant population are represented by each person in the sample. The analysis in this article uses weights, rather than sample counts, so that the information can be compared with other population-level data. It should be noted that, even when weighted to represent the wider population, the ACLD will not be the same as the full Census dataset. You can find more information about weighting, record linkage and record collection in the Methodology.

The Census asks people to identify their status as an Aboriginal and/or Torres Strait Islander person using the Standard Indigenous Question (SIQ). Whether a person identifies themselves as an Aboriginal and/or Torres Strait Islander person in the Census may change between Censuses. It may also change if they are identified by a responsible adult who is completing the Census on behalf of their household in one or more Censuses.

This article uses identification categories to explore changes in how people report their Indigenous status between Censuses. These categories are based on whether a person identified themselves as being an Aboriginal and/or Torres Strait Islander person in each of the 2011, 2016 and 2021 Censuses, or if their identification status changed in any of the three Censuses. An individual must be linked between all three Censuses to be included in this analysis.

Of those who identified as an Aboriginal and/or Torres Strait Islander person in the 2011, 2016, or 2021 Censuses:

• 63.3% identified across each of the 2011, 2016 and 2021 Censuses
• 15.8% newly identified in 2021
• 11.5% newly identified in 2016
• 7.5% previously identified in 2011 and/or 2016 but did not identify in 2021. 

Identification in the three Censuses varied by the Remoteness Area of the person's usual address in 2021. In Remote Australia, 9 in 10 (90%) of those who identified as an Aboriginal and/or Torres Strait Islander person in the 2011, 2016, or 2021 Censuses identified in all three Censuses. This is compared to 6 in 10 (62%) in Regional Australia and over 5 in 10 (55%) in Major Cities of Australia. 

People who newly identified in the 2021 Census made up:

• 19% of people who identified in Major Cities of Australia
• 16% of people who identified in Regional Australia
• 4% of people who identified in Remote Australia.

Identification as an Aboriginal and/or Torres Strait Islander person in the 2011, 2016 and 2021 Censuses varied by state and territory of the usual address in 2021. In New South Wales and Victoria, around half of people who identified as an Aboriginal and/or Torres Strait Islander person in the 2011, 2016, or 2021 Censuses identified in all three Censuses (56% and 48% respectively). In the Northern Territory, this proportion was 92%, the highest of any state or territory.

For people who identified as an Aboriginal and/or Torres Strait Islander person in the 2011, 2016, or 2021 Censuses:

• 15% in New South Wales newly identified in 2016, the highest of any state or territory.
• 13% in both Victoria and Tasmania identified in 2011 and/or 2016, but not in 2021.

The proportion of people who newly identified as an Aboriginal and/or Torres Strait Islander person in the 2021 Census varied across states and territories. In the Northern Territory, 3% of people who identified as an Aboriginal and/or Torres Strait Islander person in one or more of the 2011, 2016, and 2021 Censuses, newly identified in 2021. In both the Australian Capital Territory and Victoria, this was more than 2 in 10 (23%); the highest proportions of any state or territory.

Of the people who identified as an Aboriginal and/or Torres Strait Islander person in the 2011, 2016 or 2021 Censuses, those aged 10 to 14 years in 2021 made up the largest age group (117,445 people). Of these people, 19% newly identified as an Aboriginal and/or Torres Strait Islander person in 2021, the highest of any age group. Those aged 15 to 19 made up the second largest age group (93,930 people). Of these, 17% were newly identified in 2021. This likely reflects children being newly identified as Aboriginal and/or Torres Strait Islander people, either by themselves or by a responding adult, when they had not identified at younger ages. 

In contrast, young adults aged 20 to 24 and 25 to 29 years in 2021 were more likely to be previously identified. This change in identification may be related to those aged 20 to 29 years completing the Census for themselves for the first time.

For people aged 75 years and over who identified as an Aboriginal and/or Torres Strait Islander person in the 2011, 2016, or 2021 Censuses (20,772 people):

• 56% identified in all three Censuses, the smallest share of any age group
• 14% previously identified, the largest share of any age group
• 9% newly identified in 2016
• 19% newly identified in 2021.

Differences in identification as an Aboriginal and/or Torres Strait Islander person in the 2011, 2016 or 2021 Censuses between males and females were small. Of those who identified, 61% of males and 65% of females identified in all three Censuses. Males and females who newly identified in 2021 made up 17% and 15%, respectively, of the population who identified in one or more of the 2011, 2016 and 2021 Censuses.

This section looks at a person’s identification as an Aboriginal and/or Torres Strait Islander person over the 2011, 2016 and 2021 Censuses in relation to their partner’s identification in 2021. The person may have had the same or a different partner in 2011 and 2016. People who had an Aboriginal and/or Torres Strait Islander partner in 2021 were more likely to have identified as an Aboriginal and/or Torres Strait Islander person in each of the Censuses than people who had a non-Indigenous partner in 2021. Of those who had an Aboriginal and/or Torres Strait Islander partner in 2021:

• more than 8 in 10 (83%) identified in each of the three Censuses
• around 1 in 18 (5.5%) newly identified in 2016
• about 1 in 13 (8%) newly identified in 2021. 

Of people who identified as an Aboriginal and/or Torres Strait Islander person in the 2011, 2016, or 2021 Census and had a non-Indigenous partner in 2021:

• more than half (53%) identified in each of the three Censuses
• almost 1 in 7 (14%) newly identified in 2016
• about 2 in 10 (19%) newly identified in 2021.

The Socio-Economic Index for Areas (SEIFA) for 2021 is used by the ABS to rank areas by socio-economic advantage and disadvantage. SEIFA combines Census data such as income, education, employment, occupation, housing and family structure to summarise the socio-economic characteristics of a geographic area. Each area receives a SEIFA score indicating how relatively advantaged or disadvantaged that area is compared with all other areas across Australia. These areas are split into 5 groups, or quintiles, with each quintile having an approximately equal population. When applied to smaller populations, differences in the spread of population in the SEIFA quintiles demonstrate a difference in disadvantage or advantage relative to the national population. 

Within SEIFA, the Index of Relative Socio-economic Disadvantage (IRSD) focuses on relative socio-economic disadvantage. A low score indicates relatively greater disadvantage and a high score indicates a relative lack of disadvantage. Quintile 1 contains the most disadvantaged areas, quintile 2 contains the second most disadvantaged areas, through to quintile 5 which contains the least disadvantaged areas.

For people who identified as an Aboriginal and/or Torres Strait Islander person in each of the three Censuses, the number of those in quintile 1 was nearly 8 times greater than in quintile 5. This means that people who identified in all three Censuses were nearly 8 times more likely to live in areas of most disadvantage than in areas of least disadvantage.

There were nearly 3 times as many people in quintile 1 compared with quintile 5 for those who newly identified as an Aboriginal and/or Torres Strait Islander person in the 2021 Census. This means that people who newly identified in 2021 were almost 3 times more likely to live in areas of most disadvantage than in areas of least disadvantage.

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ABS (Australian Bureau of Statistics) (2013), ''Information Paper: Perspectives on Aboriginal and Torres Strait Islander Identification in Selection Data Collection Contexts, 2012' cat. no. 4726.0, Australian Bureau of Statistics website.

ABS (Australian Bureau of Statistics) (2021), 'Analysis: Understanding change in counts of Aboriginal and Torres Strait Islander Australians: Census', Australian Bureau of Statistics website.

Dudgeon, P, Wright, M, Paradies, Y, Garvey, D & Walker, I (2010), 'The social, cultural and historical context of Aboriginal and Torres Strait Islander Australians, in Working together: Aboriginal and Torres Strait Islander mental health and wellbeing principles and practice' Australian Institute of Health and Welfare, Canberra.

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Identification as an Aboriginal and/or Torres Strait Islander person in the Census over time, 2011 to 2021, methodology