Population pyramids are a common way to display a given group of people stratified by age and sex. They frequently appear in research studies, marketing plans, public health policy documents, and in a variety of other applications where it is important to understand the demographics of a population. With practice, it is easy to glance at a pyramid and immediately understand whether the population is expanding, contracting, experiencing a baby boom, or approaching a period of economic decline due to a change in dependency ratio.
The pyramids created by the Population Pyramid Generator show the population entered by age and sex. The percentage numbers along the side represent the amount of that sex that each age group represents. The numbers at the top display the total numbers of males and females, along with the sex ratio, calculated as the males divided by the females. The bars are a visual representation of the relative size of each age group to the others. Their size is relative to all of the other age cohorts, both male and female.