© 2006 Population Reference Bureau
A.D.2000
A.D.1000
A.D.1
1000B.C.
2000B.C.
3000B.C.
4000B.C.
5000B.C.
6000B.C.
7000B.C.
1+ million years
8
7
6
5
2
1
4
3
OldStoneAge New Stone Age
BronzeAge
IronAge
MiddleAges
ModernAge
Black Death —The Plague
9
10
11
12
A.D.3000
A.D.4000
A.D.5000
18001900
1950
1975
2000
2100
Future
Billions
Source: Population Reference Bureau; and United Nations, World Population Projections to 2100 (1998).
World Population Growth Through History
© 2006 Population Reference Bureau
Ninth
Eighth
Seventh
Sixth
Fifth
Fourth
Third
Second
First Billion
Number of years to add each billion (year)
All of Human History (1800)
130 (1930)
30 (1960)
15 (1975)
12 (1987)
12 (1999)
14 (2013)
14 (2027)
21 (2048)
Sources: First and second billion: Population Reference Bureau. Third through ninth billion: United Nations, World Population Prospects: The 2004 Revision (medium scenario), 2005.
World Population Growth, in Billions
© 2006 Population Reference Bureau
Trends in Population Growth Worldwide
Population Increase and Growth Rate, Five-Year Periods
80
8783
7976 76 75
72
0
10
20
30
40
50
60
70
80
90
1980-1985
1985-1990
1990-1995
1995-2000
2000-2005
2005-2010
2010-2015
2015-2020
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
Net population added per year Annual population growth rate
Mill
ions
Per
cent
incr
ease
per
ye
ar
Source: United Nations, World Population Prospects: The 2004 Revision (medium scenario), 2005.
© 2006 Population Reference Bureau
Millions
Annual Increase in World Population
0
10
20
30
40
50
60
70
80
90
100
1951 1956 1961 1966 1971 1976 1981 1986 1991 1996 2001 2005
Source: United Nations, World Population Prospects: The 2004 Revision, 2005.
© 2006 Population Reference Bureau
Trends in Population Growth Worldwide
Population Increase and Growth Rate, Five-Year Periods
80
8783
7976 76 75
72
0
10
20
30
40
50
60
70
80
90
1980-1985
1985-1990
1990-1995
1995-2000
2000-2005
2005-2010
2010-2015
2015-2020
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
Net population added per year Annual population growth rate
Mill
ions
Per
cent
incr
ease
per
yea
r
Source: United Nations, World Population Prospects: The 2004 Revision (medium scenario), 2005.
Notes on Trends in Population Growth Worldwide
• This figure illustrates the lag between changes in the rate of growth and the net increase in population per year.• Over the period 1985-1995, the population growth rate declined (a reflection of declining fertility), yet millions of people were added to the world’s population (which peaked around 1985, when 87 million people were added each year). • From 2000 on, the growth rate will continue to decline. Between 2015 and 2020, we will still be adding 72 million people each year. Why? Because the generation of women now having their children is very large as the result of high fertility in their mothers’ and grandmothers’ generations.
Billions
0
1
2
3
4
5
6
7
8
9
10
1950 1970 1990 2010 2030 2050
Less Developed Regions
More Developed Regions
Source: United Nations, World Population Prospects: The 2004 Revision (medium scenario), 2005.
Growth in More, Less Developed Countries
World Population Clock
Natural Increase per World
More Developed Countries
Less Developed Countries
Less Developed Countries (less China)
Year 80,794,218 1,234,907 79,559,311 71,906,587
Day 221,354 3,383 217,971 197,004
Minute 154 2 151 137
2005
Source: Population Reference Bureau, 2005 World Population Data Sheet.
Rates of birth, death, and natural increase per 1,000 population
0
5
10
15
20
25
30
35
40
1950-1955
1955-1960
1960-1965
1965-1970
1970-1975
1975-1980
1980-1985
1985-1990
1990-1995
1995-2000
2000-2005
Birth rate Death rate
Natural Increase
Source: United Nations, World Population Prospects: The 2004 Revision, 2005.
Birth and Death Rates, Worldwide
© 2006 Population Reference Bureau
• Birth rates and death rates are declining around the world. Overall economic development, public health programs, and improvements in food production and distribution, water, and sanitation have led to dramatic declines in death rates. And women now have fewer children than they did in the 1950s. • Nevertheless, if death rates are lower than birth rates, populations will still grow. • Also, it is possible for absolute numbers of births to increase even when birth rates decline.
Notes on Birth and Death Rates, Worldwide
Worldwide
0.6
0.9
1.82.0 2.0
1.3
0
1
2
3
1950-1955 1970-1975 1990-1995 2010-2015 2030-2035 2045-2050
Bill
ion
s
0
1
2
3
4
5
6
Ch
ildre
n p
er
wo
ma
n
Women 15 to 49 Average number of children per woman
Source: United Nations, World Population Prospects: The 2004 Revision (medium scenario), 2005.
Women of Childbearing Age and Fertility
© 2006 Population Reference Bureau
• The number of women in their childbearing years has increased since the 1950s and is projected to continue to increase to 2050.• The number of children per woman has declined since the 1950s and is projected to continue to decline.• Even though women have on average fewer children than their mothers, the absolute number of babies being born continues to increase because of the increases in the total number of women of childbearing age.
Notes on Women of Childbearing Age and Fertility
Life Expectancy at Birth, in Years
49
6772
76
6565
7780 82
75
Africa Asia Latin Americaand the
Caribbean
More DevelopedRegions
World
2000-2005 2045-2050
Source: United Nations, World Population Prospects: The 2004 Revision (medium scenario), 2005.
Trends in Life Expectancy, by Region
© 2006 Population Reference Bureau
• In 2045-2050, infants born around the world can expect to live an average of 75 years — up ten years from today. • Africa will experience the largest increase in life expectancy: from 49 years to 65 years. • Life expectancy varies widely by region. In more developed countries, life expectancy averages 76 years, compared with only 49 years in Africa.
Notes on Trends in Life Expectancy, by Region
Population Structures by Age and Sex, 2005 Millions
300 100 100 300300 200 100 0 100 200 300
Less Developed Regions
More Developed Regions
Male Female Male Female
80+ 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
5-90-4
Age
Source: United Nations, World Population Prospects: The 2004 Revision, 2005.
Age Distribution of the World’s Population
© 2006 Population Reference Bureau
• Sex and age distributions show that less developed countries have significantly younger populations than more developed countries.• Almost one-third of the population in less developed countries is under age 15. In contrast, less than one-fifth of the population in more developed countries is under 15.• Today there are more than 2 billion young people below age 20 in less developed regions—the age cohort that will soon become the world’s newest group of parents. • Young age structures in the less developed countries are due mainly to higher levels of childbearing in recent decades.
Notes on Age Distribution of the World’s Population
Time
Stage 1 Stage 2 Stage 3 Stage 4
Naturalincrease
Birth rate
Death rate
Note: Natural increase is produced from the excess of births over deaths.
The Classic Stages of Demographic Transition