THE STATE OF WORLD POPULATION 1998

THE NEW GENERATIONS

Era of Rapid Population Growth
Is Not Over

Falling fertility and smaller families have prompted claims that "the population explosion is over", and that there is no need to seek wider reproductive choice and slower population growth. These claims are wrong on several counts.

World population is currently growing by more than 80 million a year, compared to 58 million in 1960 at the height of the "population explosion". As the United Nations Population Fund’s The State of World Population 1998 points out, the annual rate of growth is much less (1.4 per cent, down from 2 per cent), but the base population has doubled.

There were 2.5 billion people in 1950; there will be 6 billion by mid-1999, and between 7.7 billion and 11.1 billion by 2050 according to UN projections — 9.4 billion is considered most likely. That means population may grow as much or more in the next 50 years than in the past 50.

Since the early 1960s, contraceptive use has risen five-fold, from 10-12 per cent of married couples to 60 per cent. Worldwide, the total fertility rate (TFR) has declined by half, from six children per woman to three. In some countries, couples are now having fewer than the two children they need to replace themselves in the population. But in developing countries — excluding China — women average four children, twice the level needed for a population to stabilize. In sub-Saharan Africa, the TFR is six.

Warnings of shrinking populations tend to focus on those countries whose birth rates are now at or below two children per couple, or replacement level, as is the case in most developed countries, a few rapidly industrializing countries, and China. There are currently 51 such countries, accounting for 44 per cent of the world’s population. This is projected to reach 88 countries with two thirds of the world population in 2015. But projections are educated guesses — they depend on assumptions about future behaviour which may or may not happen. One of the key assumptions about developing countries is that contraceptive use will continue to go up and fertility will continue to fall.

A focus on current birth rate leaves out of account what has happened in the past. The fact is that population growth would continue even if fertility were to fall immediately to replacement level. Because of high fertility in the recent past, a large proportion of the population in most developing countries is young. There are more than 2 billion people under age 20 in developing countries, and more young women aged 15-19 than ever before. This ensures that the number of people in their reproductive years will continue to grow for several decades, and that total births will continue to increase.

This "population momentum" accounts for up to two thirds of projected population growth globally, more in those developing countries where fertility has declined fastest. In Thailand, for instance, where three people out of ten are under age 15, the population is projected to grow by 18 per cent between 1998 and 2025, even though the average couple is having fewer than two children.

Projections of the ultimate size of the world population are very sensitive to small variations in assumptions. If, starting in 2025, global fertility were to remain at 2.2 children per woman, the population would reach 18.3 billion by 2150. On the other hand, if global fertility were 1.8 in 2025, total population in 2150 would be just 6.4 billion.

Ultimate population size depends not only on the size of completed families but on decisions about when to start them. Raising the age at which mothers have their first child from 18 to 23 would reduce population momentum by over 40 per cent.

Population momentum is not a factor in Europe because fertility has been low for a long time. But projections of shrinking populations may still be exaggerated, for two reasons:

First, projections based on below-replacement fertility leave out of account migration from higher-fertility countries. Though many countries are tightening curbs on migration, this is in response to increasing pressures from would-be migrants. It seems possible that migration to low-fertility countries will increase rather than decrease in future.

Second, the total fertility rate indicator, which uses current fertility as a guide to the future, can underestimate actual completed fertility. Future families — and populations — may be bigger than TFR indicates. TFR does not measure women’s actual experience. It is calculated by using the fertility experience of women of different ages in a recent time period to estimate how many children a woman would have if she had a similar number of children at those ages as she passed through her reproductive years.

But as fertility reaches low levels, the timing of births often changes. Women have fewer children, but they also have them later in life and in a shorter period. Measuring current births to younger women will not reflect their intention to have children later; the current experience of older women, on the other hand, will not show the children they had earlier.

For example, in France, the TFR is estimated to be around 1.63. But the most recent age-groups to have completed their fertility averaged about 2.1 children. Similarly, couples married 15-19 years in Japan have had on average 2.2 children, though TFR is 1.4.

Similarly, population projections based on current and forecast TFR can exaggerate declines unless they are designed taking into account changing fertility and marriage patterns at different ages. A small underestimate of current fertility levels can be greatly magnified when projected into the future.

The substantial reductions in fertility over the past three decades reflect changing social norms. With improving economic and social conditions, child survival rates and life opportunities, couples increasingly want smaller families and to have children later in life. But lower fertility also depends on couples having the information and services they need to effect their desires.

National programmes that provide family planning information and services and other reproductive health care have played a significant part in reducing population growth in developing countries since the 1960s, by giving people some control over family size and spacing. But many couples are still having more children than they really want.

Fertility projections used to predict declining population growth assume continued improvement in the effectiveness of reproductive health programmes. Experience shows, however, that this is not guaranteed. At times, growing demand for family planning outpaces programme capacity. As the 1994 International Conference on Population and Development recognized, improving the quality and scope of programmes will require institutional and financial commitments from both developing countries and international donors.

Enabling couples and individuals to choose the size and spacing of their families, a long-established human right, will reinforce the global trend towards smaller families and slower population growth.

— Word count: 1,100

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