USING DATA TO TRACK POPULATION TRENDS
I.
II.
Population Data
a. Includes ttal population counts and rates such as
crude birth rate, crude death rate, and so on.
b. Primary data sources include the United Nations
Statistical Office, the World Bank, the Population
Reference Bureau, and from national census counts.
c. Census counts
i. Can be unreliable in developing countries
1. Illiteracy
2. Corrupt officials
3. Accessibility
ii. In the United States
1. Decennial
2. Constitutional requirement for drawing
political boundaries
3. Important in funding and policy formulas
Crude birth rate and crude death rate
a. CBR
i. Live births in one year per 1000 people
ii. Fails to consider age structure of population
iii. Tend to be highest in least developed regions
1. Many women at reproductive age
2. High fertility rates
3. Largely agricultural economy (children =
laborers in subsistence agriculture)
iv. Religious rules may also limit birth control
(Roman Catholics and Muslims)
b. CDR
i. Deaths in one year per 1000 people
ii. Fails to consider age structure of population
c. Natural increase or decrease is difference between
birth and death rates (NI or ND= CBR – CDR)
i. CBR of 22 per 1000 – CDR of 12 per 1000 =
Natural increase of 10 per 1000 or 1%
ii. Above 2 % is considered high
iii. Determining factors
1. Economic development = access to health
care, employment and nutrition
2. Better education = lower rates of disease
3. Gender empowerment: women with more
economic and political access and
education will lower fertility rates.
4. Social and religious norms regarding
contraception
5. Public policies
a. Pronatalist – addresses the issue of
declining population by encouraging
births through subsidized child care
costs and and generous maternity
leave benefits
b. Antinatalist – addresses the issue of
overpopulation by discouraging
births with contraception, child
limits and even sterilization
III. Infant mortality
a. Deaths during first year of life per 1000 live births
b. Usually higher in developing regions due to a lack of
access to health care services
c. Rates have decreased significantly over last 50 years
IV. Life expectancy
a. Average number of years an infant newborn can
expect to live
b. Developed countries have much higher lie
expectancies than developing countries
c. Varies widely from group to group: urban, rural,
ethnicity, sex, employment, habits, associations
V.
Total fertility rate
a. Average number of children a woman will have
during her childbearing years (age 15 – 49)
b. Allows demographers to predict birth rates of a
particular group over time.
c. Replacement level fertility = slightly more than 2
but may be higher due to infant mortality.
VI. Demographic accounting equation: predicts population
change within a particular area as a function of
natural change and migration
VII. Global population growth and doubling time
a. The amount of time it will take a particular
population to double in size
b. Populations with 1% growth rate double in 70 years
c. Populations with 2% growth rate double in 35 years
d. Exponential growth, which truly began in the 1950’s
are graphed as a J-curve.
e. Recent decades have shown a reduced growth rate
creating more of an S-curve.
VIII. Population pyramids a.k.a. age-sex pyramids
a. Types
i. Rapid growth - with a wide base
ii. Stability - with a rectangular shape
iii. Decline – with a smaller base than the top
iv. Disrupted – with gaps due to drastic events
(war, disaster, policy, etc.)
b. U.S. Trends
i. Baby Boom
1. Individuals born post WWII (1946 –
1964)
2. Largest population cohort in U.S.
demographic history
3. Retirement of this generation will create
economic burdens for younger,
productive generations.
ii. Baby bust
1. Fertility rates dropped in the 1960s and
70s creating lower CBR
2. Baby boom women sought higher levels of
education, and more competitive careers
3. Many women had fewer children later in
life
IX. Dependency ratio
a. A measure of the economic impact of younger and
older cohorts on economically productive members
of a population
b. Younger cohorts are typically children under age 15
c. Older cohorts are typically retirees age 64+
X. Sustainability
a. Using resources in a manner that supplies existing
populations while not compromising availability of
resources for future generations
b. Limiting population growth relieves pressure on
future generations’ resource needs
c. In the 1994 U.N. Meeting on Population and
Development in Cairo, developing countries with
higher population growth rates criticized developing
regions for their over-consumption and argued that
they needed to focus on resource conservation.
XI. Demographic transition model: describes population
growth stabilization as a function of economic
development
a. Phases
i. Pre-industrialization: high birth and death
rates
ii. Transition to industrialization: high birth and
low death rates
iii. Mostly industrialized: birth rates drop
iv. Highly developed: population growth is stable
or negative
b. Downfalls of the demographic transition model
i. Designed to describe the demographic history
of Europe
ii. Export of medical technology and public health
policies to developing regions since the 1950’s
slowed death rates without decreasing birth
rates
iii. Developing world’s population is exploding as
it is industrializing
XII. Impact of HIV/AIDS
a. Creates a major and dramatic exception to recent
population growth trends particularly in the
developing world
b. Fourth most common cause of death world wide,
will likely become the worst epidemic in history
c. AIDS and Sub-Saharan Africa
i. Expected loss of life from the disease = 68
million (55 million between 2000 and 2020)
ii. In 2006, 65% of the 40,000,000 people across
the globe diagnosed with HIV lived in SubSaharan Africa
iii. In some countries 1 in 4 people carry the virus
iv. In Botswana, life expectancy has been cut in
half from 70 to 35.