Responses to the Ancestry question are classified to the Australian Standard Classification of Cultural and Ethnic Groups (ASCCEG). This classification is revised as part of a periodical review process based on real world change. Changes to the ancestry classification and coding index have significantly affected the data for some responses.

See also the Ancestry fact sheet.

For the ancestry question in the 2011 Census, responses of Sri Lankan (or similar) were coded to Sri Lankan. In 2006 these responses were coded to Sinhalese. There were over 75,000 such responses in 2011.

Ancestry Multi Response – coding for Sri Lankan and Sinhalese
Ancestry 2001 Census 2006 Census 2011 Census
Sinhalese 58,602 73,849 22,945
Sri Lankan .. .. 75,136

.. not applicable

As a result of the revision of the classification, there is an apparent drop in numbers of people with Sinhalese ancestry in the 2011 Census data.

Additionally, there has been a change to the classification for those who reported as having Tamil ancestry in 2011. This response has been split into three with the following counts for 2011.

Ancestry Multi Response - coding for Tamil
Ancestry 2011 Census
Sri Lankan Tamil 5,182
Indian Tamil 509
Tamil, nfd 13,735

nfd: not further defined

References

Information about the Ancestry question, in Ancestry topic, in the Information Paper: Census of Population and Housing: ABS Views on Content and Procedures, 2011 (cat. no. 2007.0).

Information about the review of ASCCEG, in Australian Standard Classification of Cultural and Ethnic Groups (ASCCEG), 2011 (cat. no. 1249.0).