Our Crowded Future
Stan Becker, ProfessorDepartment of Population, Family and
Reproductive Health
Summer 2008
Ninth
Eighth
Seventh
Sixth
Fifth
Fourth
Third
Second
First Billion All of Human History (1800)
130 (1930)
30 (1960)
15 (1975)
12 (1987)
12 (1999)
14 (2013)
14 (2027)
21 (2048)
World Population Growth, in BillionsNumber of years to add each billion (year)
Sources: First and second billion: Population Reference Bureau. Third through ninth billion: United Nations, World Population Prospects: The 2004 Revision (medium scenario), 2005.© Population Reference Bureau 2006.
World Population Growth
0
2,000
4,000
6,000
8,000
10,000
12,000
1750 1800 1850 1900 1950 2000 2050
More Developed Countries Less Developed Countries
2007:6.6 Billion
Population growth, 1750-2050
Sources: Before 1950: PRB estimates; 1950-2050: adapted from UN, World Population Prospects: The 1996 Revision, 1998 (medium scenario).
World Population Clock 2005
1371512154Minute197,004217,9713,383221,354Day
71,906,58779,559,3111,234,90780,794,218Year
Less Developed Countries (less China)
Less Developed Countries
More Developed CountriesWorld
Natural Increase per
Source: Population Reference Bureau, 2005 World Population Data Sheet.
Trends in Population Growth WorldwidePopulation Increase and Growth Rate, Five-Year Periods
8087
8379 76 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.
Population Trends by Region 1950-2050
0
1
2
3
4
5
6
Asia Africa LatinAmerica
Europe NorthAmerica
Bill
ions
195020002050 (projection)
Source: United Nations 2001
U.S. Population growth
• Net Immigration• At least 800,000 legal immigrants• Approximately 400-500,000 net
undocumented• Relatively small number of emigrants• Approximately 4.1 million births• Approximately 2.4 million deaths• NET GROWTH= ABOUT 3 MILLION
Source: “International Migration 2006” UN Population Division Wall Chart, 2006.
Source: “International Migration 2006” UN Population Division Wall Chart, 2006.
Some Simple Mathematics
Crude birth rate (CBR) = Births x 1000Total population
Crude death rate (CDR) = Deaths x 1000Total population
Crude rate of increase (CRI) = Births-deaths x 1000 Total population
World population increase = 78 million per yearTotal world population = 6.6 billion
So 78 million x 1000 = 11.8 CRI or 1.18% growth per year6.6 billion
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
Population by Age: Developing World
0 200 400 600 800
0-4
10-14
20-24
30-34
40-44
50-54
60-64
70-74
Age
Population (millions)Source: United Nations 2001
1950 1975 2000 2025 2050
Old Age Dependency Ratio by Region
0
0.1
0.2
0.3
0.4
0.5
1950 1975 2000 2025 2050Year
Rat
io
Source: United Nations 2001
Europe
Asia
L. America
Africa
N.America
Median age of the population for various countries
Country Median ageWorld 27.8Japan 43.5Italy 42.5Belgium 41.1USA 36.6Taiwan 35.5Sri Lanka 30.0Turkey 28.6South Africa 24.3Egypt 24.2Ethiopia 18.0Malawi 16.7Uganda 14.9
Source: World Urbanization Prospects, The 2007 Revision Executive Summary, UN Division of social and economic affairs
Urban PopulationPercent
29
15 17
5347
37 37
76
55
42
74
85
54
61
82
World Africa Asia Latin Americaand the
Caribbean
MoreDeveloped
Regions
1950 2000 2030
Source: United Nations, World Urbanization Prospects: The 2003 Revision (medium scenario), 2004.
Trends in Urbanization, by Region
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.Source: Population Reference Bureau, 2008
The Classic Stages of Demographic Transition
Total Fertility Rate (TFR) by RegionPast Estimates and Projections
0
1
2
3
4
5
6
7
1950 1975 2000 2025 2050
Birt
hs p
er w
oman
Source: United Nations 2001
L.America
AfricaAsia
N.America
Europe
Patterns of Fertility DeclineAverage number of children per woman
0
2
4
6
8
10
1950–1955 1960–1965 1970–1975 1980–1985 1990–1995 2000–2005
Source: United Nations, World Population Prospects: The 2004 Revision, 2005.
Uganda
Kenya
Colombia
South Korea
Reaching Replacement FertilityAverage number of children per woman
5.6
7.0
5.4
6.4
5.7
7.3
1.9 2.0 2.1 2.0 1.9 2.0
Azerbaijan Chile Iran Mauritius Thailand Tunisia
1960-1965 2000-2005
Source: United Nations, World Population Prospects: The 2004 Revision, 2005.
Intermediate Fertility VariablesExposure factors
1. Proportion marriedDeliberate marital fertility control factors
2. Contraception3. Induced abortion
Natural marital fertility factors4. Lactational infecundability5. Frequency of intercourse6. Sterility7. Spontaneous intrauterine mortality8. Duration of the fertile period
EASTERN EUROPESOUTHERN EUROPE
EAST ASIAWESTERN EUROPE
NORTHERN EUROPENORTHERN AMERICA
SOUTH AMERICACARIBBEAN
SOUTHEAST ASIACENTRAL
SOUTHERN AFRICASOUTH CENTRAL ASIA
NORTHERN AFRICAWESTERN AFRICA
SUB-SAHARAN AFRICAEASTERN AFRICAWESTERN AFRICA
MIDDLE AFRICA 6.3
5.55.7
1.82.0
2.4
3.4
5.5
2.8
2.52.7
2.8
3.03.1
1.6
1.31.4
1.6
59%
58%54%
50%
51%22%25%
13%25%
58%
74%82%
73%
75%55%
84%
63%
Total Fertility Rate Contraception Prevalence
66%
# of children per woman percentage
Source: PRB, 2007 World Population Data Sheet
Pill8%IUD
14%
Injectable or Implant
3%
Male Condom5%
Female Sterilization
21%
Not Using39%
Other Modern Methods
1%
Traditional Methods
7%Male Sterilization
3%
Note: Total exceeds 100 due to rounding.Source: United Nations Population Division, World Contraceptive Use 2005.
Married or In-Union Women of Reproductive Age Using Family Planning, 1999
Childbearing and Women’s EducationAverage number of children per woman, by educational level, 2000-2004
Sources: Demographic and Health Surveys: Kenya 2003, Madagascar 2003-4, Egypt 2000, Bangladesh 2004, Bolivia 2003.
6.7 6.5
4.13.6
6.8
5.54.9
3.2 3.13.8
5.7
3.42.52.5
3.3
0
12
34
56
7
Kenya Madagascar Egypt Bangladesh Bolivia
No formal education Primary completed Secondary completed
Family Planning and Women’s Education
8 5
50 49
18
29
19
5647
30
52
28
58
48 46
010203040506070
Kenya Madagascar Egypt Bangladesh Bolivia
Per
cent
No formal education Primary completed Secondary completed
Percent women ages 15-49 using family planning, by educational level, 2000-2004
Sources: Demographic and Health Surveys: Kenya 2003, Madagascar 2003-4, Egypt 2000, Bangladesh 2004, Bolivia 2003.
Life Expectancy Trends in Africa
30
40
50
60
70
80
90
1925 1950 1975 2000 2025 2050
Year
s
South Africa
Africa
Source: Population Division of the Department of Economic and Social Affairs of the United Nations Secretariat (2007). World Population Prospects: The 2006 Revision, Population Database. New York: United Nations.
Components of Population Growth Developing World
0
2
4
6
8
10
1950 2000 2050 2100
Popu
latio
n si
ze (b
illio
ns)
Source: Bongaarts and Bulatao 1999
Standard Projection Effect of
Fertility abovereplacementDeclining
Momentummortality
This calculation uses the global average per capita area demand (EF). For 1999 that worldwide average EF was 2.3 hectares per person. This is significantly lower than the average EF in industrialized countries such as the United States (9.7 hectares per person), the United Kingdom (5.4 hectares per person) and Germany (4.7 hectares per person) (Living Planet Report 2002). Note for our readers in the U.S. 1 hectre = 2.5 acres.
If all the world used resources at the rate that the U.S. does, we would need more than THREE earths to sustain life.
I = P*A*T formula
I = impact of humans on the environment/ecosphere
P = populationA = affluence per capitaT = impact of technology to produce that
affluence
Introductory Courses inPopulation and Health
Principles of Population Change
Demographic Methods for Public Health
Application of Population Data for Policy andPractice (New Course)
Other courses in Population and Health
Title Quarter
Social and economic aspects of humanfertility
1
Couples and reproductive health 1Biosocial population research 2Fundamentals of life tables 3Dynamics of population aging 3Migration and health (new course) 3Economics of gender and family 4Poverty, economic development and health 4Methods and measures in population studies 4
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