Home CyberTour Treasury Survey Game InfoDesk LA2K
Return to Overview
 RealAudio Balloon

Demographic Background Resources


Advances in public health and control of infectious diseases has led to increased life expectancy in most parts of the world. Thus, the number of elderly people in the world is rapidly increasing. In discussing trends in the number of older persons, an arbitrary decision has been made to define the elderly segment of the population in terms of persons aged 60 and over. In the context of developed countries , increasing life expectancy and improving physical and mental we-being at older ages may make this threshold seem inappropriately low for demarcating the beginning of old age. These countries usually tabulate data for ages 65 years and above. Conversely, lower life expectancy and patterns of premature aging may make this threshold seem high in developing countries. These countries tabulate data for those 55 years and above. However, to simplify the discussion of worldwide trends and to permit cross-national comparisons, the General
Graph: World's 20 Oldest Countries
World's 20 Oldest Countries (Source: U.S. Bureau of the Census)
Assembly of the United Nations Resolution 35/129 of December 11, 1980 endorsed the report of the secretary-general on the draft program for the World Assembly on the Elderly (A/35/130), in which the elderly population is defined as persons aged 60 and over.
A distinction must be made between "growth in numbers of older persons" and the "aging of a population" associated with changes in the proportionate weight of the elderly. These two phenomena result from different population dynamics. The growth in numbers of older persons simply refers to the actual number or projected number of people over a certain age. The aging of populations (the process through which a population as a whole becomes older) is a ratio. It refers to the proportion of persons over a certain age (e.g. 60) compared to either the rest of the population (e.g. everyone 59 and younger) or to some other specific age group. Sometimes the number of elderly is compared to children under 15, median age, or the proportion of the population above the age corresponding to a remaining life expectancy of, say 10 or 15 years. What is important is that each of these measures would indicate different degrees of aging for the same population. Generally these statistics are used to give a picture of the "weight" of the elderly in a population. Sometimes you will read that different countries have the fastest "aging of their population"— this can happen because different numbers are selected for the ratio, depending on the issue being considered. The process of population aging is primarily determined by fertility (birth) rates and secondarily by mortality (death) rates.
Populations with high fertility rates tend to have low proportions of older persons and vice-versa. Demographers use the term "demographic transition" to refer to a gradual process wherein a society moves from a situation of high rates of fertility and mortality to one of low rates of fertility and mortality. This transition is characterized first by declines in infant and childhood mortality as infectious and parasitic diseases are eradicated. The resulting improvement in life expectancy at birth occurs while fertility tends to remain high, thereby producing large birth cohorts and an expanding proportion of children relative to adults. Whole populations begin to age when fertility rates decline and mortality rates at all ages improve. A picture of "young" countries would be a pyramid, where the wide base is the number of births and infants. As populations age, the pyramid shape begins to change. Sometimes demographers refer to an aging population as having the shape of an "inverted pyramid", where the weight will be on the top, and the base becomes smaller or narrower. The term epidemiological transition refers to a long-term change in major causes of death, from infectious and acute disease to chronic and degenerative diseases. The epidemiological transition or process results in demographic changes or demographic transition. Modernization and industrialization, when societies move from developing to developed, are generally associated with epidemiological transitions and the resulting demographic transition. They also contribute to trends such as "out migration" from rural areas and urbanization— factors which are associated with older populations sometimes being clustered. For example, when young people continually leave rural areas to find jobs in cities, the population of the rural area becomes increasingly elderly.
Map: Percent Aged 65 and Over
Percent Aged 65 or Over: 2025 (Source: U.S. Bureau of the Census)

United Nations population projections estimate that by 2025 only 25% of the world’s population will be in the 0-14 age group and nearly 14% will be in the 60+ group. The UN also projects that the weight of children in the populations of less developed regions will simultaneously decline to 26%, with the weight of the elderly reaching nearly 12%. In more developed regions the weight of the older population will surpass that of the young, with 20% of their inhabitants in the 0-14 age group and 23% aged 60 or over. At the same time, absolute numbers of persons 60+ world-wide are projected to jump from 376 million in 1980 to 1,121 million in 2023, with more than 70% living in less developed regions.
Age specific projections suggest that there will be a fivefold increase in persons aged 60 and over between 1950 and 2025. Within the elderly population itself, the older age groups are expected to show even faster growth, that is a seven fold increase in persons aged 80 and over between 1950 and 2025. The number of elderly persons throughout the world is expected in increase from 214 million in 1950 to over 1 billion by the end of the first quarter of the twenty-first century, while the number of octogenarians (80+) jumps from 15 million to 111 million.

-