# XXii INTRODUCanON

close to 92 million people annually, with a projected all-time high increase of ovcr 92 million around 1998. Thc projections show that it will take only 11 years to add anothcr billion to the five billion people of 1987. Despite a declining trend in fertilityt population growth in the short term will clearly be very high.

After the turn of the century, population will continue to grow, although at a somewhat slower rate. The seven billion mark will be reached before the end of the first decade of the 21st century. Because of differences in growth rates between less developed and more developcd countries, 84.1 percent of world population will be living in what are currcntly less developcd countries by 2025, up from 75.7 percent in 1985.

These projections differ only slightly from U.N. (1989) and previous World Bank projections (Zachariah and Vu 1988). Figure 6 shows that the estimate of the popuilation in less developed countrics by 2025 is .5 percent lower than the U.N. estimate and 3 percent higher than the previous World Bank estimate. Figure 7 shows that the estimate of the po.pulation in more developed countries by 2025 is I percent lower than the U.N. estimate and identical to the previous World Bank estimate. These differences are due not only to differences in procedures for projecting vital rates but also to slightly different current population and vital rate estimates.

Continents. Current and projected population and growth rates by continent are shown in Table 5. In these groupings of countries, North and South America are considered together, the U.S.S.R. is combined with Europe, and Australia is combined with the Pacific under oceania. (The population of Antarctica is insignificant.) The percentage distribution of world population by continent is represented for 1985, 2000, and 2025 in Figures 8-10.

Asia, with the two most populous countries in the world, accounts for 58 percent of world population, and currently contributes 63 percent of the annual increase, or about 55 million people. By 2025, Asia will still be adding to world population about 45 million people annually. However, by that year, the proportion of world population in Asia is expected to be no different from the 1985 proportion, despite a projec:ed 74 percent increase in the Asian population from 1985 to 2025.

Table 5 Total Population, Annual Increase, and Growth Rates for Continents, 1985-2025

|||Popula|tion<br>(mil|lions)|||Ann|ual inc|rease<br>(|<br>millio|ns)||Growth|rate (p|ercen|t)|
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|||Ame-|<br>|Europe,||||Ame-||Europe,|||Ame-||Europe|,|
|Year|Africa|rica|Asia|USSR|Oceania|Period|Africa|rica|Asia|USSR|Oceania|Africa|rica|Asia|USSR|Oceania|
|1985|<br>559|667|2,823|771|25|1985-1990|<br>18.2|10.9|55.4|3.3|0.4|3.02|1.57|1.87|0.42|1.63|
|1990|<br>651|721|3,100|787|27|1990-1995|<br>20.5|10.9|57.1|2.7|0.4|2.93|1.45|1.76|0.34|1.59|
|1995|<br>753|775|3,385|801|29|1995-2000|<br>23.3|10.2|55.7|2.4|0.4|2.88|1.27|1.58|0.30|1.40|
|2000|870|826|3,664|813|31|2000-2005|<br>26.0|9.4|53.9|2.0|0.4|2.79|1.10|1.42|0.25|1.21|
|2005|1,000|873|3,934|823|33|2005-2010|<br>27.8|9.0|51.1|1.6|0.4|2.60|1.00|1.26|0.20|1.04|
|2010|1,139|918|4,190|831|35|2010-2015|<br>29.2|8.8|48.9|1.4|0.3|2.41|0.94|1.14|0.17|0.89|
|2015|1,285|962|4,434|838|36|2015-2020|<br>30.1|8.3|47.8|1.1|0.3|2.21|0.84|1.05|0.13|0.72|
|2020|1,435|1,003|4,673|844|38|2020-2025|<br>30.4|7.2|45.6|0.8|0.2|2.02|0.71|0.95|0.10|0.59|
|2025|1,587|1,040|4,901|848|39||||||||||||