|World population (millions) by region, 1972-2000
World population is currently growing at 77
million a year, with two-thirds of the growth in Asia and the Pacific
Source: compiled from United Nations Population
World population increased from about 3.85 billion
people in 1972 to 6.1 billion in mid-2000 (see figure right), and is currently
growing by 77 million people a year (UNFPA 2001). Most of the growth is
concentrated in developing regions, with nearly two-thirds in Asia and
the Pacific. Six countries accounted for 50 per cent of the annual growth:
India (1 per cent), China (2 per cent), Pakistan (5 per cent), Nigeria
and Bangladesh (4 per cent each) and Indonesia (3 per cent) (United Nations
Population Division 2001).
The population of industrialized regions, currently 1.2 billion, is expected
to change little in the next 50 years while that of the developing regions
is projected to increase from 4.9 billion in 2000 to 8.1 billion by 2050
(United Nations Population Division 2001). This difference is mainly due
to levels of fertility. Less developed countries recorded fertility at
3.1 children per woman over the period 1995-2000, while developed countries
recorded fertility at 1.57 children per woman over the same period - well
below the replacement level of 2.1 children per woman (UNFPA 2001).
The gap in life expectancy between the developing and the more developed
regions narrowed from 22 years in 1960 to less than 12 in 2000. Between
1995 and 2000, life expectancy in the industrialized regions was estimated
to be 75 years, compared to about 63 years in developing regions (United
Nations Population Division 2001). As world fertility continues to decline
and life expectancy rises, the population of the world will age faster
in the next 50 years than during the past half-century (United Nations
Population Division 2001). Nevertheless, the emergence of HIV/AIDS in
the 1970s has depressed life expectancy in the most affected countries,
and the disease is now the fourth most common cause of death worldwide.
More than 60 million people have been infected with HIV since the 1970s,
and 20 million have died. Of the 40 million living with HIV/AIDS worldwide,
70 per cent are in sub-Saharan Africa where it is the leading cause of
death (UNAIDS 2001). Compared to Africa, the relative impact of the HIV/AIDS
epidemic in most other regions of the world is still low.
There have been notable population movements over the past 30 years due
to rapid urbanization, international migration and the movement of refugees
and displaced persons. The number of people living outside their own countries
rose from 84 million in 1975 to an estimated 150 million people at the
end of the 20th century (UNDP 1999, UNHCR 2000). The number of refugees
rose from 2.7 million in 1972 to a peak of 18.3 million in 1992, and stood
at 11.7 million at the end of 1999 (UNHCR 2000). By 2001, an estimated
22 million people 'of concern' were numbered among the world's refugees,
returnees and persons displaced within their own countries (UNHCR 2001).
The more developed regions are expected to continue being net receivers
of international migrants, with an average gain of about two million a
year over the next 50 years. Because of low fertility in recipient countries,
this migration will have a significant impact on population growth in
the developed regions (United Nations Population Division 2001).