what it is and how it works. canada 1961 consists of two back-to- back bar graphs population...

What it is and how it works

Canada 1961

Consists of two back-to-back bar graphs

population plotted on the X-axis and age on the Y-axis, in five-year age groups (cohorts).

Males are shown on the left and females on the right

Measured by raw number or as a percentage of the total population.

Canada 1961

Where are you represented? Males? Females?

Oldest at top Youngest?

Each age group called a “cohort”

Expansive broad base rapid rate of population

growth low proportion of older

people. A steady upwards

narrowing shows that more people die at each higher age band.

This type of pyramid indicates a population in which there is a high birth rate, a high death rate and a short life expectancy.

LEDC’s for the most part

Stationary narrow base and

roughly equal numbers in each age group, narrowing at the older ages.

Scandinavian countries

Constrictive- a high

proportion of aged persons and declining numbers of Births.

- Germany, Italy

Population Pyramids are useful for:

Used to find the number of economic dependents in a population. Under 15 and over 65 (those who have the option of

retirement)

Dependency ratio = % under 15 + % over 64% 15-64

Used to observe natural increase, birth/mortality rates, breakdown by age range within a population