Each year Australia's population increases as a result of both natural increase (births minus deaths) and net overseas migration (NOM). While natural increase has remained relatively stable, NOM has been far more volatile and in recent years has accounted for over half of the population growth at the national level.
In 2008-09, the preliminary estimate of NOM was the highest on record for a financial year at 298,900 persons, representing 65% of Australia's population growth for the year.
Net interstate migration (NIM) in 2008-09 was a major source of population loss for South Australia, New South Wales, and the Australia Capital Territory, subtracting 24% (4,700 persons), 17% (19,800 persons) and 14% (800 persons) respectively from their total population growth.