A wide base shows a large number of children (high birth rate). There are less baby girls than baby boys, but boys have a higher rate of infant mortality.
Indents show higher death rates than normal (war, famine, disease) or through emigration.
A narrow shape at the top shows a low proportion of people living into old age and a high death rate. Women live longer than men.
A narrow base shows a small number of children (low birth rate). Less baby girls than baby boys, but boys have a higher infancy mortality rate.
Indents show higher death rates than normal (war, famine, disease) or through emigration. Bulges show either a period of immigration or baby boom years before.
A broad shape at the top shows a hogh proportion of people living longer. Women live longer than men.
Stage 1 - High Stationary: High birth rate; rapid fall in each upward age group due to high death rates; short life expectancy.
Stage 2 - Early Expanding: High birth rate; fall in death rate as more living in middle age; slightly longer life expectancy.
Stage 3 - Late Expanding: Declining birth rate; low death rate; more people living to old age.
Stage 4 - Low Stationary: Low birth rate; low death rate; higher dependency ratio;longer life expectancy.
Stage 5 - Contracting Declining: Birth rate below death rate; Population declining; Increasing old age dependency; Pyramid is top heavy.