graphical illustration showing distribution of age groups in a population
A population pyramid is a graph. It has two back-to-back bars. These bars show the population in groups of ages, with woman in one side and man in the other side.
The pyramids show the age distribution of the place, which can help in understanding and predicting the development of a country.
There are three types of population pyramids:
- Stationary pyramid shows a constant population, with equal birth rate and death rate
- Expansive pyramid shows a growing population
- Constrictive pyramid shows a shrinking population
In this type of graph, a wide base means a very high birth rate and a narrow base means a low birth rate.