Health & Aging

A country’s stage of the demographic transition determines the percentage of people in different age groups. A country in stage 2 of the demographic transition typically has a relatively high percentage of young people, whereas a country in stage 4 has a relatively high percentage of elderly people. The percentage of different age groups helps to explain a country’s distinctive health challenges.

Caring for Older People

Life expectancy is the average number of years an individual can be expected to live, given current social, economic, and medical conditions. Life expectancy at birth measures the average number of years a newborn infant can expect to live at current mortality levels. People on average live much longer in wealthy countries than in poorer ones. Babies born today can expect to live to 81 in Europe, but to only 60 in sub-Saharan Africa.

Life Expectancy At Birth, 2018

Percent Over 65 BY U.S. State

As countries progress through the demographic transition, they face increasing percentages of older people who need adequate levels of income and medical care after they retire from their jobs. In the United States, the percentage of the population over 65 varies widely; the highest percentages are in states to which many older people migrate and in states from which many younger people leave.

The “graying” of the population places a burden on governments in developed countries to meet these needs. The potential support ratio (also known as the elderly support ratio) is the number of working-age people (ages 15 to 64) divided by the number of persons 65 and older

Potential Support Ratio

Pause & Reflect

1 Approximately what will the U.S. potential support ratio be in 2050?

2 What could the U.S. do between now and 2050 to raise its potential support ratio?

The world’s potential support ratio is currently around 9, meaning that there are 9 people of working age for every elderly person. In 2050, the ratio is expected to decline to around 4, meaning that there will be only 4 people of working age available to support elderly people who have retired from work. Thus, as the ratio gets smaller, fewer workers are available to contribute to pensions, health care, and other support that older people need.

Pause & Reflect 2.3.3

If the potential support ratio is declining, does that mean the percentage of elderly people is increasing or decreasing?

Caring for Younger People

Developing countries in stage 2 of the demographic transition have higher percentages of young people than do countries in stage 4 (Figure 2-40). This is a consequence of the higher CBR and TFR in stage 2 countries as well as the lower life expectancy. Worldwide, 26 percent are under age 15. Those under 15 comprise 16 percent of the population in developed countries, 28 percent in developing countries, and 43 percent in sub-Saharan Africa.

Population Under AGE 15, 2018

Comparing Young and Old

A population pyramid is a bar graph that displays the percentage of a place’s population for each age and gender. A country that is in stage 2 of the demographic transition, such as The Gambia, has a pyramid with a broader base than that of a country in stage 4, such as Denmark, indicating a higher percentage of young people. In contrast to The Gambia’s more evenly tapering pyramid, the highest levels of Denmark’s pyramid are wider on the right because in Denmark, women live longer than men

The large percentage of children in sub-Saharan Africa strains the ability of these relatively poor countries to provide needed services such as schools, hospitals, and day-care centers. On the other hand, the “graying” of the population places a burden on developed countries to meet their needs for income and medical care after they retire from jobs.

The dependency ratio is the number of people who are too young or too old to work compared to the number of people in their productive years. Dependents are normally classified as people under age 15 and over age 65. The larger the dependency ratio, the greater the financial burden on those who are working to support those who do not. The dependency ratio is 52 percent in Europe, compared to 85 percent in sub-Saharan Africa.