Understanding and using Ancestry data

• The ancestry question captures information that can provide a good indication of a person’s ethnic background when used together with other variables (such as Country of birth of person (BPLP), Country of birth of mother (BPFP) and Country of birth of father (BPMP)).
• A person’s ancestry is not necessarily connected with their birthplace – instead, it relates to the cultural groups they most closely identify with.
• It is useful to identify distinct ethnic or cultural groups within Australia, such as Maoris or Australian South Sea Islanders, and groups which are spread across multiple countries, such as Kurds. Country of birth alone cannot identify these groups.
• The ancestry question is one of the few multi-response questions on the Census form. Up to two responses are allowed. Should a person provide more than two answers, only the first two are processed.
• For the first time the 2021 Census included mark boxes for both Aboriginal and Torres Strait Islander ancestries. For people completing the Census online and who identified as an Aboriginal and/or Torres Strait Islander person, these new response categories were shown at the top of the list. More information is available in Aboriginal and Torres Strait Islander ancestries.
• Further information about Ancestry data and concepts can be found in the Ancestry Statistical Standard.

The Census asks people to provide up to two ancestries. Instructional text on the form suggests people consider the ethnic origins of their parents and grandparents. In 2021, more than 300 different ancestries were reported.

Four ancestry variables are created from responses to the ancestry question on the Census:

• Ancestry 1st response (ANC1P)
• Ancestry 2nd response (ANC2P)
• Ancestry multi response (ANCP)
• Ancestry one or two response indicator (ANCRP)

Key features of these variables:

• Where a person cannot provide the same response for ANC1P and ANC2P, the response is only recorded once.
• There is no option to rank the answers to the ancestry question, so where a person reports two ancestries, they both are treated equally.
• Reported ancestries are allocated to the ANC1P and ANC2P variables based on the order the responses appear on the Census; mark box responses are processed first, and then written responses. Where a person reports more than two ancestries, only the first two mentioned are processed into ANC1P and ANC2P.
• Not stated is only used for ANC1P.
• Not applicable is only used for ANC2P and provides a count of people who did not provide a second ancestry.
• ANC1P Not stated and ANC2P Not applicable include imputed records. More information on imputation is available in the 2021 Census Dictionary.
• The Ancestry Multi Response (ANCP) variable combines the responses from ANC1P and ANC2P. This counts the total number of ancestry responses.
• The Ancestry one or two response indicator (ANCRP) allows us to understand whether a person provided one or two responses to the ancestry question.
• The ANC1P and ANC2P variables can be cross tabulated to examine ancestry combinations. Examples of how to use these variables are provided below.
• Ancestry data can be accessed in Find Census data.

The following tables demonstrate outputs for the ANC1P and ANC2P response.

In Table 1 you see:

• counts of the number of people who reported Australian, German and Other Ancestries as their first response
• those who did not provide a response to the ancestry question (Not stated)
• the Total is the sum of all people.

Similarly, in Table 2 you see:

• counts of the number of people who reported Australian, German and Other Ancestries as their second response
• those who did not provide a second response (Not applicable)
• the Total is the sum of all people.

The greatest confusion for users of ancestry data relates to the Ancestry multi response variable (ANCP). When it is added to a table and all the individual ancestries are summed, a total count of responses - not people - is produced. As each person can provide up to two ancestries, the total count of responses for all ancestries exceeds Australia’s total population.

However, when using ANCP to look at a particular ancestry, the story changes: the count of responses is also the count of people. This is because a person can only state a particular ancestry once (either as ANC1P or ANC2P).

In Table 3a you see:

• counts of the number of people who reported Australian and German ancestries. ANCP is the sum of Australian and German from ANC1P and ANC2P and is a count of the number of responses for each of these ancestries.
• Other ancestry codes from ANC1P and ANC2P do not add up to the same amount as the ANCP multi-response. This is because any person in this example that provides two different ancestries which are neither Australian nor German would only be counted once in the Other ancestry category for ANCP.
• counts for the number of people who did not provide a response (Not stated – only obtained from ANC1P) and people who did not provide a second ancestry (Not applicable – only obtained from ANC2P).
• the Total row counts the total number of people who provided information in the table. It does not equal the sum of all the rows in the table, because the rows represent the number of responses.
• people can report up to two ancestries (for example, someone might have reported having Australian ancestry and German ancestry) which means they would be counted twice in the ANCP variable in the above table.

Using the ANCP data from Table 3a as a base, Table 3b provides an example of how to calculate the percentage of the population that responded to Australian and/or German ancestry.

In Table 3b you see:

• 29.9%, or 7,596,753 people responded with an Australian ancestry – regardless of whether the Australian ancestry response was captured in ANC1P or ANC2P.
• 4.0% or 1,026,138 of people responded with German ancestry – regardless of whether the German ancestry response was captured in ANC1P or ANC2P.
• 77.7%, or 19,746,275 people responded as having Other ancestries. Note, people who responded with Australian or German ancestry may also be counted in this figure because it is a count of responses. For example, if someone responded Australian for ANC1P and New Zealander for ANC2P, they appear in both the Australian and Other categories in the above table.
• the counts for each ancestry category in ANCP are the number of responses, not the number of people, as respondents can provide up to two ancestries using ANC1P and ANC2P. The sum of these responses will not equate with the Total of this table, which is the total population. Total population should be used to calculate proportions.

Anyone who reported two ancestries is considered to have a combined ancestry. Combined ancestries can be examined in the 2021 Census data.

If you want to know how many people reported both Maori and Australian ancestry, or both Australian and New Zealander ancestry, you require a table which cross-tabulates people’s first ancestry response by their second response.

In Table 4, by running ANC1P by ANC2P, you can see the counts of people with combined ancestries. Using the ANC2P Not applicable column, you can also identify the number of people with a single ancestry of Maori, Australian or New Zealander.

In Table 4 you see:

• the number of people who stated Maori as their only ancestry (45,312), from looking at the cross tabulation of Maori for ANC1P with Not applicable for ANC2P.
• 5,538,503 people stated two ancestries - neither of which was Australian, New Zealander or Maori. This is determined by looking at the cross-tabulation of All other ancestries for ANC1P with All other ancestries for ANC2P.
• 84,841 people (16,534 + 68,307) who stated New Zealander and another ancestry that was neither Australian nor Maori. This is determined by adding up the cross tabulation of New Zealander and All other ancestries for ANC1P and ANC2P.
• 6,234 (3,058 + 3,176) people who stated the two ancestries: New Zealander and Maori. This is determined by adding up the cross tabulation of New Zealander and Maori for ANC1P and ANC2P.
• if we want to know the total number of people who only stated one ancestry (14,286,081), you first find the cross tabulation of Not stated for ANC1P and Not applicable for ANC2P (1,584,164) and subtract this from the Total for Not applicable (15,870,245).

As a comparison, the Ancestry Multi Response (ANCP) variable provides a count of responses for each ancestry (Australian, Maori and New Zealander), regardless of whether this was from ANC1P or ANC2P. People who reported two of these ancestries would be counted twice in Table 5 below.

In Table 5 you see:

• counts of the number of people who reported Australian, Maori and New Zealander ancestries - regardless of whether they were processed ANC1P or ANC2P. This is also the number of responses for these individual ancestries.
• the Total produced is a count of the people who provided the information in the table. It is not a total of all the numbers above it - that would be a total of responses (and would be equal to 7,970,322).

This is a new variable for 2021, allowing data users to understand whether a person provided one or two responses to the ancestry question.

This variable is derived from responses to the ancestry question. People can provide up to two ancestries. When a person reports one ancestry, they are coded to One response and when a person reports two ancestries, they are coded to Two responses. Where a person does not answer the question, they are coded to Not stated.

In Table 6 you see:

• 3,855,816 people provided one ancestry response as either Australian, New Zealand or Maori.
• 4,014,037 people provided two ancestry responses, where the first or second response was Australian, New Zealand or Maori.
• the Two response column total (4,014,037) is not the sum of the rows above it. This is because a person in this column has provided responses to two of the ancestry responses listed in the table and is therefore counted in each category.
• there were 203,512 people who responded as having New Zealand ancestry.
• most people (160,764) who responded as having New Zealand ancestry, provided two ancestry responses - that is, New Zealand and another ancestry.
• 45,312 people who responded Maori provided only one ancestry response. This number aligns with the calculation method in Table 4.
• 7,869,856 people provided information in this table. It is not the total of all the numbers above it, that would be a total of responses (7,970,322).
• all people in this table answered the Ancestry question - that is, Not stated equals zero.

The ancestry question records association with ancestries, ethnic origins and cultures. The intent of the question is to capture the cultural context in which people were raised, however, some people may respond according to how they may identify with a particular cultural group.

Ancestry in the Australian context is complex as there are many people with origins and heritage that do not, in practice, relate to their current ethnic identity.

People can identify with any ancestry they choose – regardless of their origin. Additionally, the Census may be completed by one household member on behalf of others. The way people respond can also be influenced by changes in culture.

A major advantage of the Ancestry variable is that it can measure an association with ethnic and cultural groups which cannot be readily identified using country of birth, religion and language variables. When Ancestry data is used alone, it represents a broad measure of cultural diversity. Ancestry data used in conjunction with Country of birth of person (BPLP), Religious affiliation (RELP) and Language used at home (LANP) variables provides additional information about a person’s ethnic origin. It may be of most value for some analytical purposes when the population of interest is restricted to persons born overseas, or who have one or more parents born overseas.

Please see information in Aboriginal and Torres Strait Islander ancestries for advice on using the ancestry variables in analysis of the Aboriginal and Torres Strait Islander population.

The ancestry question was asked in 1986, 2001, 2006, 2011 and 2016. Over time it has experienced changes in both form design and survey mode (online or paper form). These changes can impact the way people respond to the question. For example, between the 2006 and 2011 censuses, the number of people with Scottish ancestry increased from 1.5 million to around 1.8 million. This was likely related to Scottish being introduced as one of the mark box options on the Census form during the 2011 Census, in addition to Scottish migration to Australia during those five years.

The 2021 Census included mark boxes for both Aboriginal and Torres Strait Islander ancestries. For people completing the Census online and who identified as an Aboriginal and/or Torres Strait Islander person, these new response categories were displayed at the top of the list. More information is available in Aboriginal and Torres Strait Islander ancestries.

Updates were also made to the examples provided for other ancestries, and the order of response categories based on the 2016 Census results. Find out more about the history and changes to the ancestry question in the 2021 Census Dictionary.

Ancestry responses are coded using the Australian Standard Classification of Cultural and Ethnic Groups (ASCCEG). For 2021, Norfolk Islander (code 1105) was added to ASCCEG following Norfolk Island’s inclusion in the 2016 Census.

When comparing ancestry Census data over time, refer to ASCCEG and past Census forms for any changes or issues affecting a specific population.

For further assistance with using the Ancestry variables, please see the ABS website for our contact details.