Population statistics are measures of the size, growth, composition and geographic distribution of the population as well as the components that shape population change - notably births, deaths and migration. Population statistics underpin discussion on a wide range of issues of concern to the community, including immigration, cultural diversity, ageing and population sustainability. Statistics on population trends assist governments in developing social and economic policy. Changes in Australia's population affect policy areas such as health, education, housing, the labour market and the environment.
There are also important legislative requirements for the Australian Bureau of Statistics (ABS) to produce population estimates. The legislation which determines the distribution of state, territory and local government grants uses ABS population estimates as one of the bases for calculation. Similarly, population estimates are used to determine the number of seats each state and territory is entitled to in the House of Representatives.
The Census of Population and Housing is the principal source of information about Australia's population. It has been held every five years since 1961 with the most recent census conducted in August 2001. The next census is due to be held in August 2006.
The census provides a base from which Australia's estimated resident population is calculated. The census count of the population is adjusted for visitors from overseas, Australian residents temporarily overseas on census night and an estimate of the number of people missed in the census and those counted more than once. To obtain estimated resident population figures for dates between censuses, births and net overseas migration are added and deaths are subtracted. For estimates at the state and territory level, interstate migration estimates are also applied.
The Population chapter contains four articles: Ageing Australians; Urban and non-urban population; Recent fertility trends; and Future living arrangements.