1. Demographic Transitions
Population Pyramids

2. Population Pyramids – Shows the percentage of the total population, usually in 5 year age groups, with youngest on bottom, oldest on top.
Every country or regions stage of demographic transition gives it a distinctive population structure. Shape is determined primarily by crude birth rate in the community.

3. US Population Pyramid

4. Demographic Transition and Age
Age Distribution -Extremely important in understanding similarities and differences among countries.
Dependency Ratio – The most important factor when talking about age distribution.
Three Age Groups
0-14
15-64
65+
Stages and age – As people pass through the stages of demographic transition, the percentage of elderly people increases. The higher the stage, the higher the number of dependants, and the more money required to take care of the population.

5. Demographic Transition and Sex Ratio
Sex Ratio – The number of males per hundred females. Varies and in general more males than females are born, but males have higher death rates. As age goes up, so does the ratio of females.

6. Countries in different stages
Stage 1 – None
Stage 2 – Cape Verde
Antimalarial campaign
Environmental issues
Broad base

7. Stages 3 & 4 Stage 3 – Chile Stage 4 – Denmark
Outside of Europe and North America
Vigorous Government funded family planning
Stay due to reversal of policy
Stage 4 – Denmark
Roughly equal CBR and CDR
Zero population growth
Percentages of youth and elderly are the same