Population pyramid
![This distribution is named for the frequently pyramidal shape of its graph.](/Images/godic/202412/20/Population_pyramid_example.svg2253.png")
![Population pyramids for 4 stages of the demographic transition model](/Images/godic/202412/20/DTM_Pyramids.svg2253.png")
![Median age by country. A youth bulge is evident for Africa, and to a lesser extent for South and Southeast Asia and Central America.](/Images/godic/202412/20/Median_age2253.png")
![A world map showing countries by fertility rate, according to the CIA World Factbook's 2015 data.
7-8 Children
6-7 Children
5-6 Children
4-5 Children
3-4 Children
2-3 Children
1-2 Children
0-1 Children](/Images/godic/202412/20/Countriesbyfertilityrate.svg2253.png")
A population pyramid, also called an age pyramid or age picture diagram, is a graphical illustration that shows the distribution of various age groups in a population (typically that of a country or region of the world), which forms the shape of a pyramid when the population is growing. It is also used in ecology to determine the overall age distribution of a population; an indication of the reproductive capabilities and likelihood of the continuation of a species.