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# **OVERVIEW** OF TRENDS AND PROJECI1ONS

We eview recet trends and projections for the future, focusing, fist, on the world and geogmphic regions; and second, on World Bank regions and on countries grouped by income; and finaly on petcular countries or economies.

Rewen **t** rends, from 1975 to 1990, are striling because of the rapid changes occurring in some countrie and the absence of change in others. Some sountries, especially in Southeast Asia and Latin America, experienced sharp declines in fertility, large increases in life expectancies, and a slowdown in population growth. Others, especially in Sub-Saharan Africa, saw persistent high levels of fertility, mortality, and population growth. Still others, mainly in Europe, had stable fertility below replacemnt (i.e., below the level required for each generation to replace itself in the succeeding generation) and slow population growth during the enti-e period.

The projections carry forward, and work out the future implications of these trends country by country but also iniroduce some dramatic changes, such as eventual fertility transition in **Sub-Sahamn Africa.**

# World and Regions

The aggreptes we consider here, besides the world u a whole, are more developed and les developed countries; five major geographic regions, corresponding roughly to continents, but with North and South America considered together, the U.S.S.R. combined with Europe, and the Pacific treated with Australia s Oceania; and some subcontinental regions. For all these aggregates, Tables 1-5 give estimates of current and projected population size and growth; current and projected fertility **and** mortality rates; current and projected age structure and dependency ratios; and projected long-run treads. These subjects will be considered in order.

# **_Pepulaoi Sim_** _and Growth_

The world population in mid-1990 is estimated at 5.28 billion. It is growing at almost the same rate as in 1975, but the number of people added each year has risen continuously since then. Since the mid-1970s, world population growth has been virtually constant at just over 1.7 percent annually, but the number of people added in 1990 is up 20 million from 1975, to 91 million. The rate of growth will fall to 1.4 percent annually at the beginning of the 21st century. In spite of this, the annual net increase in the number of people will be larger in the year 2000 than in 1990, around 92 million people. Average annual additions to the world population are projected to increase between 1990 and 2005. They will begin a steady decline around 2020. Annual additions will be esentially stable at around 91.5 million between 2005 and 2015.

Of the 440 million increase in the world population between 1985 and 1990, 406 million (92 percent) was contributed by less developed countries which, in 1990, contained 77 percent of the world populition. The 1985-90 growth rates for less developed and more developed countries were widely different, **at** 2.1 and 0.6 percent respectively. The less developed country growth rate is falling and by the beginning of the 21st century will have declined by close to 20 percent, to 1.7 percent per annum. Nevertheless, the differences in growth rates between less developed and more developed countries mean that 79 percent of the world population will be living in what are currently less developed countries by the beginning of the 21st century, up from 77 percent in 1990. By 2025, **84 percet** of the world population will be living in areas currently classified **as** less developed.

At these levels of aggregation, these projections differ only slightly from the U.N. (1990) **_an_ lat** year's World Bank projections (Bulatao et al. 1990), as Figure 1 shows. The projected **less**