Heath and Aging

Why Population Aging Matters: A Global Perspective

Trend 1: An Aging Population

Since the beginning of recorded human history, young children have outnumbered older people. Very soon this will change. For the first time in history, people age 65 and over will outnumber children under age 5 (Figure 1). This trend is emerging around the globe. Today almost 500 million people are age 65 and over, accounting for 8 percent of the world’s population.

By 2030 the world is likely to have 1 billion older people, accounting for 13 percent of the total population. While today’s proportions of older people typically are highest in more developed countries, the most rapid increases in older populations are occurring in the less developed world. Between 2006 and 2030, the number of older people in less developed countries is projected to increase by 140 percent as compared to an increase of 51 percent in more developed countries.

Population aging is driven by declines in fertility and improvements in health and longevity. In more developed countries, declines in fertility that began in the early 1900s have resulted in current fertility levels below the population replacement rate of two live births per woman. Perhaps the most surprising demographic development of the past 20 years has been the pace of fertility decline in many less developed countries. In 2006, for example, the total fertility rate was at or below the replacement rate in 44 less developed countries.

Most of the more developed nations have had decades to adjust to this change in age structure (Figure 2). For example, it took more than a century for France’s population age 65 and over to increase from 7 to 14 percent of the total population. In contrast, many less developed countries are experiencing rapid increases in the number and percentage of older people, often within a single generation. The same demographic aging process that unfolded over more than a century in France will occur in two decades in Brazil. In response to this “compression of aging,” institutions must adapt quickly to accommodate a new age structure. Some less developed nations will be forced to confront issues, such as social support and the allocation of resources across generations, without the accompanying economic growth that characterized the experience of aging societies in the West. In other words, some countries may grow old before they grow rich.

Year Age<5 Age 65+
1950 13.4 5.2
1960 14.2 5.3
1970 14.1 5.5
1980 12.2 5.9
1990 11.9 6.2
2000 10.1 6.9
2010 9.3 7.7
2020 8.5 9.4
2030 7.6 11.8
2040 7.1 14.3
2050 6.7 16.1

Source: United Nations Department of Economic and Social Affairs, Population Division. World Population Prospects. The 2004 Revision. New York: United Nations, 2005.


Country Number of years for population age 65+ to increase from 7% to 14%
France (1865-1890) 115
Sweden (1890-1975) 85
Australia (1938-2011) 73
US (1944-2013) 69
Canada (1944-2009) 65
Hungary (1941-1994) 53
Poland (1966-2013) 47
UK (1930-1975) 45
Spain (1947-1992) 45
Japan (1970-1996) 26


Country Number of years for population age 65+ to increase from 7% to 14%
Azerbaijan (2000-2041) 41
China (2000-2026) 26
Jamaica (2008-2033) 25
Tunisia (2008-2032) 24
Sri Lanka (2004-2027) 23
Thailand (2003-2025) 22
Brazil (2011-2032) 21
Colombia (2017-2037) 20
Singapore (2000-2019) 19

Source: Kinsella K, Gist Y. Older Workers, Retirement, and Pensions. A Comparative International Chartbook. Washington, DC: U.S. Census Bureau and U.S. National Institute on Aging, 1995; and U.S. Census Bureau. International Data Base. Available at: http://www.census.gov/ipc/www/idbnew.html. Accessed January 8, 2007.

Publication Date: September 2011
Page Last Updated: October 7, 2011