NEWS
9 Billion?
IN 1900, THERE WERE 1.6 BILLION PEOPLE ON EARTH.
By 2000, that number had skyrocketed to 6.1 billion. This astounding rate
of growth has slowed, but the trend is still heading dramatically upward.
It varies substantially by region, however, with the less developed coun-
Population is growing—fast ...
Going up. The world has never seen anything like the population explosion of the past century. Four
billion people have been added to the planet since 1950, and the time it takes to add 1 billion people has
dropped to 13 years. World population could reach 9.3 billion by 2050, according to U.N. projections.
World Population Growth, 1950–2050 (medium variant)
Historic and Projected Population Growth
10
10
9
Population (billions)
8
7
6
13
years
To add the next
1 billion people
5
4
3
2
1
0
1+ Million years
6000 B.C.E.
4000 B.C.E.
2000 B.C.E.
C.E. 1
9.3 Billion
9
8 Billion 2024
7 Billion 2011
6 Billion 1999
5 Billion 1987
4 Billion 1974
3 Billion 1960
2 Billion 1930
1 Billion 1800
India
8
7
China
6
5
Africa
4
3
Other less developed countries
2
1
More developed countries
0
1950
C.E. 2000
1970
1990
2010
2030
Behind the growth.
Much of the population growth
of the past 50 years is due to the
spectacular gains in life expectancy in developing countries,
reflecting advances in public
health and medicine.
540
Constant
25
Constant fertility variant
High-fertility variant, 2.5 children
20
Population (billions)
The United Nations has peered out
to 2100, but those projections are
even more uncertain than those
for 2050. The medium variant
most commonly used assumes the
average woman in 2100 will have
two children. If she had half a child
more, or less, the picture would
change dramatically. And if fertility remained constant at current
levels …
U.N. Population Projections, 1950–2100
Medium-fertility variant, 2.0
TFR* 2.5
Low-fertility variant, 1.6
15
*Total fertility rate: the average number
of children women would bear in their
lifetime if the birth rate of a particular
year were to remain unchanged.
10
2.0
1.6
5
0
1950
1975
2000
2025
2050
2100
2075
SOURCE: UNPD, 2011
Trends in Life Expectancy at Birth, 1950 and 2010
73.4
80
60
Years
Different assumptions,
different scenarios.
2050
SOURCES: UNPD, 2011
SOURCES: CARL HAUB, POPULATION REFERENCE BUREAU (PRB), 2010; U.N. POPULATION DIVISION (UNPD), 2011
51.3
40
55.2
38.2
69.0
65.6
75.4
1950 –1955
68.7
2005–2010
78.2
67.9
47.7
42.9
20
0
Latin Amer. and
the Caribbean
Africa
Asia
Europe
N. America
World
SOURCE: UNPD, 2011
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tries growing rapidly and the more developed countries growing slowly,
if at all. World population is expected to pass 7 billion in late October
and is projected to top 9 billion by 2050; the latest U.N. projections put
it at about 10 billion in 2100. In truth, no one knows exactly how high
population will grow or when it might flat-line. All population projections
are uncertain, as they are entirely dependent on assumptions about the
future—for instance, how many children a woman will have 20 or 30 years
hence. In that sense, these numbers can be considered best scientific
guesses, not destiny. What’s more, the further out one looks, the cloudier
these projections become. Still, they offer a window into what the world
might look like in 2050.
–LESLIE ROBERTS
SPECIALSECTION
... But more slowly than in the recent past
Tipping point. The period of most rapid population growth is
More women, fewer kids. The global fertility rate has dropped
behind us. Since its peak from 1965–70, the growth rate has declined,
falling roughly by half in 40 years as women have had fewer children.
from 5 to 2.5 in roughly 50 years, and the average woman in developing
countries (outside of China) now has three children, down from six.
Population Growth Rate, 1950–2010
Global Decline in Fertility, 1950–2010
6
1.5
1.0
0.5
1955
1960
1965
1970
1975
1980
1985
1990
1995
2000
2005
2010
5
4
3
2
1
0
1950
1955
1960
1965
1970
1975
1980
1985
1990
1995
2000
2005
2010
SOURCE: UNPD, 2011
SOURCE: UNPD, 2011
Stark contrasts. But that downward trend masks sharp regional differences. Since 1970,
Asia and Latin America have seen the steepest drops; in sub-Saharan Africa, fertility remains
high, in part reflecting desired family size.
Fertility Rates Vary Across the Globe
Total Fertility Rate, 2010
Fewer than 1.5 births per woman
1.5–2.1 births per woman
2.2–2.9 births per woman
3.0–4.9 births per woman
5.0 or more births per woman
SOURCE: PRB, 2010
Strong predictors. High fertility rates are associated with poverty
By the numbers
and low levels of educational attainment for girls.
How Many Children Do Women Say Are
“Ideal”? (selected countries and dates*)
9.1 5.3 3.2
3.0 2.4 1.6
Niger
Egypt
Uganda
U.K.
Jordan
Austria
*Niger 2006, Uganda 2006, Jordan 2007,
Egypt 2008, U.K. 2006, Austria 2006
Fertility and Education, 2007
Fertility and Poverty, 2007
Percentage of girls enrolled in secondary school
Percentage of population living on <$2 per day
100
100
80
80
60
60
40
40
20
20
0
0
1
2
3
4
5
Total fertility rate
6
7
8
0
0
SOURCES: DEMOGRAPHIC AND HEALTH SURVEYS; EUROBAROMETERS
1
2
3
4
5
Total fertility rate
6
7
8
SOURCE: PRB, 2007
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2.0
0.0
1950
Less developed countries
(excluding China)
World
More developed countries
7
Total fertility rate
Growth rate (% per year)
2.5
Where is it growing?
Different rates. Virtually all population growth from now until 2050 will occur in developing
Percent
Population
Growth,
2005–2050
100+
26–99
1–25
<1
Projected Population
Growth by Country
2005–2050
SOURCE: PRB, 2011
Sheer numbers.* Because of sub-Saharan Africa’s high fertility rate, the fastest growth will occur there. But even with its slower growth
rate, Asia—largely India and China—will still account for the bulk of the world’s population in 2050.
LATIN
AMERICA
2010 2050
*Numbers in thousands
AFRICA
2010 2050
1,022,234
Population
ASIA
2010 2050
2,191,599
Projected
4,164,252
Population
EUROPE
2010 2050
5,142,220
Projected
738,199
Population
719,257
Projected
590,082
Population
NORTH
AMERICA
2010 2050
750,956
Projected
344,529
Population
446,862
Projected
SOURCE: UNPD, 2011
Young and growing; aging and stable. In developing countries, the large pro-
By the numbers
portion of young people ensures rapid population growth. The aging population in more
developed countries, with few future parents, spells little or no growth.
Age
85+
80–84
75–79
70–74
65–69
60–64
55–59
50–54
45–49
40–44
35–39
30–34
25–29
20–24
15–19
10–14
5–9
0–4
Developing
Countries
2010
300
Developed
Countries
2010
Males
Females
200
100
0
100
Population (millions)
200
300 300
200
100
0
100
200
300
Population (millions)
43%
3%
16%
16%
SOURCE: UNPD, 2011
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Population <15,
sub-Saharan Africa
Population 65+,
sub-Saharan Africa
Population <15,
Europe
Population 65+,
Europe
SOURCE: PRB, 2010
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countries—with the largest growth concentrated in the poorest countries of the world.
SPECIALSECTION
The World Ahead
By the numbers
2:1
6:1
Population of developing to developed
countries, 1950
Population of developing to developed
countries, 2050
SOURCE: UNPD, 2011
A tale of two countries. A look at Nigeria and Japan today suggests what’s ahead. Given Nigeria’s
high birthrate and large number of women of childbearing age, the population is expected to more than
double by 2050, while the population of Japan is expected to decline.
Age
85+
80–84
NIGERIA
158
5.7
6,700,000
43
3
47
75
500,000
326
Nigeria
2010
0–4
15
10
5
0
5
10
Population (millions)
JAPAN
Population 2010 (millions)
Lifetime births per woman
Annual number of births
Percentage of population below age 15
Percentage of population over age 65
Life expectancy at birth
Infant death per 1000 births
Annual number of infant deaths
Population 2050 (millions)
15
By the numbers
20
15
2010
2050
Number of people that developing countries could be adding each year in 2050
5
0
5
10
Population (millions)
15
17
11
9
9
10
4
5
4
4
2
Number of people that developed countries could be adding each year in 2050
0
World
More developed
Less developed
SOURCE: PRB, 2010
12 Biggest Cities
1975
Percentage Residing in Urban Areas, 1950–2050
City
90
80
70
60
50
40
30
World
More developed
Less developed
20
10
0
1960
1970
1980
1990
2000
2010
Least developed
SOURCE: PRB, 2010
fastest rate of urbanization occurring in less developed countries.
1950
0-4
10
Number of Working-Age Adults
per Older Adult, 2010 and 2050
City bound. More and more people will be living in cities and towns, with the
100
Males
Females
SOURCES: (CHART) PRB, 2010; (POPULATION PYRAMIDS) UNPD, 2011
countries will not have enough workers to support the
higher costs of their aging populations. Developing countries with young populations will not have enough jobs.
International migration is set to increase.
Million
Japan
2010
15
Higher costs, fewer workers. In 2050, developed
37
0
Age
85+
80–84
127
1.4
1,090,000
13
23
83
2.6
2,830
95
2020
2030
2040
2050
Tokyo
N.Y.-Newark
Mexico City
Osaka-Kobe
São Paulo
L.A.-Long Beach
Buenos Aires
Paris
Kolkata
Moscow
Rio de Janeiro
London
SOURCE: UNPD, 2009
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2025
Population
(millions)
26.61
15.88
10.69
9.84
9.61
8.93
8.74
8.56
7.89
7.62
7.56
7.55
City
Population
(millions)
Tokyo
Delhi
Mumbai
São Paulo
Dhaka
Mexico City
N.Y.-Newark
Kolkata
Shanghai
Karachi
Lagos
Kinshasa
37.09
28.57
25.81
21.65
20.94
20.71
20.64
20.11
20.02
18.73
15.81
15.04
SOURCE: UNPD, 2009
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The Demographic Divide