The provision of regular estimates of the growth, size and structure of the Australian population is one of the core functions of the Australian Bureau of Statistics (ABS). These official population estimates, termed the estimated resident population (ERP), are used for a wide variety of purposes including the distribution of Australian Government funds to state, territory and local governments, as well as in the determination of the number of seats for each state and territory in the House of Representatives.
At the national level there are two components of Australia's population growth: natural increase (the number of births minus the number of deaths) and net overseas migration (NOM - the net gain or loss of population through immigration to Australia and emigration from Australia). Population growth at the state and territory level has three components: natural increase, NOM and net interstate migration (NIM - the net gain or loss of population through the change of a person's place of usual residence from one state or territory to another state or territory).
1 United Nations Population Division, World Population Prospects: The 2010 Revision. Accessed 17 May 2011. <back