UN Report: The World Population in 2300
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Population Division of the Department of Economic and Social Af-
fairs of the United Nations Secretariat
December, 2003
Report available online at:
http://www.un.org/esa/population/publications/longrange2/Long_range_report.pdf
Website:
http://www.un.org/esa/population/publications/longrange2/longrange2.htm
The Population Division of the Department of Economic and So-
cial Affairs of the United Nations has prepared for the first
time a set of population projections to the year 2300 for each
country of the world. All projection scenarios share the same
assumptions about the steady decline of mortality after 2050 and
the consequent increase of life expectancy. In addition, in all
scenarios, international migrationis assumed to be zero after
2050.
In terms of fertility, the medium scenario assumes that the to-
tal fertility of each country will reach below replacement lev-
els and remain at those levels for about 100 years, after which
it will return to replacement level and remain there until 2300.
In the high scenario total fertility after 2050 is assumed to be
a quarter of a child higher than in the medium scenario and to
remain constant at 2.35 children per woman when the medium sce-
nario stabilizes at replacement level. Similarly, in the low
scenario total fertility is assumed to be 0.25 of a child lower
than in the medium scenario and to remain constant at 1.85 chil-
dren per woman when the medium scenario settles at replacement
level.
Some of the main findings yielded by a comparison of these sce-
narios are summarized below:
1. According to the medium scenario, world population rises from
6.1 billion persons in 2000 to a maximum of 9.2 billion persons
in 2075 and declines thereafter to reach 8.3 billion in 2175.
The return to replacement level fertility coupled with increas-
ing longevity in the medium scenario produces a steadily in-
creasing population after 2175 that reaches 9 billion by 2300.
If the effects of increasing longevity are counterbalanced by
fertility, population size remains constant at 8.3 billion from
2175 to 2300 as in the zero-growth scenario
2. Future population size is highly sensitive to small but sus-
tained deviations of fertility from replacement level. Thus, the
low scenario results in a declining population that reaches 2.3
billion in 2300 and the high scenario leads to a growing popula-
tion that rises to 36.4 billion by 2300 (table 1).
3. In the medium scenario, most of the expected population in-
crease between 2000 and 2300 occurs in the less developed re-
gions, whose population rises form 4.9 billion in 2000 to 7.7
billion in 2300. Although the population of more developed re-
gions also increases, the change is considerably less (from 1.2
billion in 2000 to 1.3 billion in 2300).