ABOUT THIS RELEASE
This publication is part of the Demography Working Paper series.
This report contains a review of possible sources for the Australian Bureau of Statistics' (ABS) internal migration estimates for the period 2001-2006. It is an update of Demography Working Paper 96/1 - Evaluation of Administrative Data Sources for Use in Quarterly Estimation of Interstate Migration Between 1996 and 2001. The characteristics of each data source have been assessed against criteria which define ideal internal migration data characteristics and are detailed in separate sections of this report. Attachment A contains recommendations from Demography Working Paper 96/1 and subsequent follow-up action.
The ABS publishes quarterly estimates of the population for each Australian State and Territory (unless specified otherwise, for the remainder of this paper the term state refers to Australia's states and territories). The ABS also prepares annual population estimates by Local Government Area (LGA) and Statistical Local Area (SLA). The population bases on which these estimates and projections are prepared are Australia's quinquennial Censuses of Population and Housing. Preparation of postcensal estimates at the State level have been based on component (administrative records) methods principally because of ready access to quality births, deaths and international migration data. Australia does not keep administrative records relating directly to internal population migration. Over time, the ABS has used a number of administrative data sources to estimate quarterly interstate migration, including electoral roll registrations, family allowance payments and, for 1996-2001, Health Insurance Commission (Medicare) data supplemented by Defence Force data.
The quality of Australia's postcensal population estimates at the state level has principally reflected the quality of indirect estimation of interstate migration.
state population estimates are of high accuracy (the 1991-96 average absolute intercensal error at the state level was 0.4%), the exception being those for the Northern Territory which had an 1991-96 intercensal error of -2.9% The accuracy of 1996-2001 interstate migration estimates using Medicare data supplemented by Defence Force data and a new estimation model will only be known when 2001 Census results are available and the intercensal error is determined. Details of the model are contained in Demography Working Paper 99/2 - Estimating Interstate Migration, 1996 - 2001. Other information on interstate migration estimates is contained in Demographic Estimates and Projections: Concepts, Sources and Methods (ABS Catalogue No. 3228.0).