4. Doubling Time
Doubling time= time it takes for a population to
double
70
=number of years
for population to
% rate of population growth double
5. Demographic Transition Model
• Outlines natural stages of growth and
development
• Demographer tool to analyze and understand
population numbers and change
7. Demographic Transition Model
• Stage 1- high birth, high death=small growth
– High infant mortality
– Low life expectancy
– Common a few hundred years ago, and in
developing countries today
8. Demographic Transition Model
• Stage 2- High birth, low death= population
explosion
– Medical & scientific advances
• Vaccines, drinking water, sewage systems
• 1800s
9. Demographic Transition Model
• Stage 3- low death, declining birth
– Social programs, industrialization, urbanization=
smaller families
10. Demographic Transition Model
• Stage 4- low birth, low death=slow population
growth
– Changing role of women Lower birth
rates
– Family planning programs
– Some African countries, birth rates still high
– Sub-Saharan Africa- HIV= high death
11. Demographic Transition Model
• Stage 5- birth rate lower than death rate
• Future, however some European nations and Japan
starting to enter this stage
12. Population Pyramids
• Analyze individual region population growth
development trends
• Data organized in cohort groups
• Another demographer tool
• Created by graphing a series of horizontal bar
graph lives at intervals of 5 years
• Shape- demographer classifies pyramid into
four major categores
13. P. Pyramids- Early Expanding
1) EARLY EXPANDING
- Wide base= high birth rate
- Narrow top= short life expectancy
*few countries today fall in this category
14. P. Pyramids- Expanding
2) EXPANDING
- Wide base= high birth rates
- Middle expands= improved medical care,
modern hygiene, improved diet
15. P. Pyramids- Stable
3) STABLE
- Birth rate falls= changing attitude towards
family (Education programs, changing societal
attitudes, economic factors)
- Death rate lowered= improved medical care
16. P. Pyramids- Contracting
4) Contracting
- Very low birth rate= women in work
force, child-rearing is
expensive, contraception, state encourages
small families
- Death rate continues to decrease
- Life expectancy increases
26. Developing/Developed Regions
Developing regions: historically uneven
economic and population growth levels
Early expanding and expanding p.pyramids
Developed regions: relatively wealthy and stable
in economic growth
Stable & contracting p.pyramids
27. Dependency
Dependency: measure of the population of
people who are too old or too young to work
- require governmental support
Dependency ratio:
% of young dependents + % of old dependents
divided by the percentage of people aged 15-
64
28. Canada’s Stats
2011- Estimations
Population Growth Rate: approximately .8%
Age structure: 0-14 years: 15.7% (male
2,736,737/female 2,602,342)
15-64 years: 68.5% (male 11,776,611/female
11,517,972)
65 years and over: 15.9% (male
2,372,356/female 3,024,571) (2011 est.)
29.
30. Canadian Stats
Estimated that by 2041- 23% population 65+
- Affects government spending (healthcare) &
immigration rates
Conclusions: Entering DTM Stage Four,
Stabalizing
