Overview
Population ageing is constituted by a shift in the distribution of a country's population towards greater ages. Thus an increase in the population's mean or median age, a decline in the fraction of the population composed of children, or a rise in the fraction of the population that is elderly are all aspects of population ageing.Population ageing is a highly generalized process. It is most advanced in the most highly developed countries. Among the countries currently classified by the United Nations as more developed (with a population of 1.2 billion in 2005), the median age of the population rose from 29.0 in 1950 to 37.3 in 2000, and is forecast to rise to 45.5 by 2050. The corresponding figures for the world as a whole are 23.9 for 1950, 26.8 for 2000, and 37.8 for 2050. In Japan, one of the fastest ageing countries in the world, in 1950 there were 9.3 people under 20 for every person over 65. By 2025 this ratio is forecasted to be 0.59 people under 20 for every person older than 65.
The sources of population ageing lie in two (possibly related) demographic phenomena: rising life expectancy and declining fertility. An increase in longevity raises the average age of the population by raising the number of years that each person is old relative to number of years in which he is young. A decline in fertility increases the average age of the population by changing the balance of people born recently (the young) to people born further in the past (the old). Of these two forces, it is declining fertility that is the dominant contributor to population ageing in the world today.
More specifically, it is the large decline in the total fertility rate over the last half century that is primarily responsible for the population ageing that is taking place in the world’s most developed countries. Because many developing countries are going through faster fertility transitions, they will experience even faster population ageing than the currently developed countries in the future.
Canada has the highest per capita immigration rate in the world, based largely on the rationale of countering population ageing. The C. D. Howe Institute, a conservative think tank, has suggested that immigration can not be used a viable means of countering population ageing.
Ageing around the world
Asia and Europe are the two regions where a significant number of countries face severe population ageing in the near future. In these regions within twenty years many countries will face a situation where the largest population cohort will be those over 65 and average age will be approaching 50.Most of the developed world (with the notable exception of the United States) now has sub-replacement fertility levels, and population growth now depends largely on immigration together with population momentum which arises from previous large generations now enjoying longer life expectancy.
Ageing, Well-being and Social Policy
The effects of an ageing population are considerable. Economically, older people are more likely to be saving money and less likely to be spending it on consumer goods. This leads to lower interest rates and disinflationary or even deflationary pressure. Some economists (Japan) are seeing advantages in this evolution, notably the possibility to go further in automatisation and technological development without the burden of social effects from reducing the wage labour force and unemployment. They emphasise a shift from GDP to Personal well being. It is also a start to reverse the evolution to world overpopulation.Population ageing also puts pressure on public finances. The largest area of expenditure in many countries is now health care and the cost of health systems will increase dramatically as populations age, a situation which will face many governments with hard choices between higher taxes, a change in tax systems (f.i. from labour to consumption) or a reduced government role in providing health care.
The second largest expenditure of most governments is education and these expenses will tend to fall with an ageing population, although this may be partly offset by the increasing proportion of the young population who continue into tertiary education.
Social security systems have also begun to experience problems. Earlier defined benefit pension systems are experiencing sustainability problems due to the increased longevity. The extension of the pension period was not paired with an extension of the active labor period or a rise in pension contributions, resulting in a decline of replacement ratios. In recent years, many countries adopted policies to strengthen the financial sustainability of pension systems, although the challenges regarding pension adequacy remain.
See also
- Ageing
- Ageing of Europe
- Average lifespan
- Birth rate
- Ecological footprint
- Gerontology
- Life expectancy
- Life extension
- List of life extension-related topics
- Longevity
- Maximum lifespan
- Senescence
References
- Gavrilov L.A., Heuveline P. Aging of Population In: Paul Demeny and Geoffrey McNicoll (Eds.) The Encyclopedia of population. New York, Macmillan Reference USA, 2003, vol.1, 32-37.
- United Nations, 2005, Human Development Report 2005, Oxford, Oxford University Press.
- United Nations, World Population Prospects: The 2004 Revision Population Database, Population Division, 2004.
- Weil, David N., “The Economics of Population Aging” in Mark R. Rosenzweig and Oded Stark, eds., Handbook of Population and Family Economics, New York: Elsevier, 1997, 967-1014.
External links
- Council of the Ageing Australia
- Aging of Population
- CoViVE Consortium Population Ageing in Flanders and Europe
- Population Aging Resources Directory
- Population Aging International News
- New Books on Population Ageing
- UN Programme on Ageing
- David N. Weil. 2006. Population Aging.
- Jill Curnow. 2000. Myths and the fear of an ageing population
- Judith Healy. 2004. The benefits of an ageing population (link permission and copyright see discussion page)
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Last updated on Monday March 03, 2008 at 17:58:07 PST (GMT -0800)
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