Journal of Population Research

, Volume 32, Issue 3–4, pp 187–213 | Cite as

Alternative state and national projections of Australia’s very elderly population

  • Wilma TerblancheEmail author


Growing very elderly populations (ages 85+) have significant implications for income support, aged care and health care and accurate projections are essential for proper planning and budgeting. Unfortunately, retrospective assessments of the ABS’ population projections revealed large errors in very elderly projections, largely due to inaccurate mortality rate forecasts. Erroneous official population estimates and death rates for the high ages also contributed to projection errors. This paper presents alternative projections of Australia’s very elderly population at a state and national level based on methods found to be simple and reliable. Adult death rates by age and sex were extrapolated assuming constant geometric rates of decline and input into a cohort-component population projection model. Australia’s very elderly population is expected to grow rapidly over the next 30 years, from 430,000 in 2012 to almost 1.5 million in 2042. As a percentage of the total population, the very elderly is expected to increase from 1.9 % in 2012 to 4.2 % in 2042. Centenarians are expected to increase from almost 3500 to over 15,000. South Australia’s very elderly population is projected to grow the least and Western Australia’s the most. Male numbers are expected to grow faster than females, resulting in increasing sex ratios. Projected very elderly numbers in 2042 are 13 % higher than official projections. ABS projections of centenarians are, however, 55 % higher. The methods used in this study are simple and have been shown to produce reliable projections. The projections presented here will facilitate effective planning for, and funding of the income and service needs of Australia’s very elderly.


Very elderly Population projections Australia Centenarians Nonagenarians States 



This paper was completed while the author was a PhD student at the University of Queensland. She gratefully acknowledges receipt of a UQ scholarship. The author is also grateful for helpful comments received from Dr Tom Wilson, as well as from an anonymous reviewer.


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© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  1. 1.Business SchoolBond UniversityGold CoastAustralia

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