Population pyramids show the number of males and females, by age groups, who live in a community at a given moment. These diagrams allow us to easily compare demographic differences between metropolitan areas, rural towns, and reservations. They illustrate the tendency of big cities to have many residents of working age, while rural small towns have growing populations of elderly residents, and reservations have relatively more young children and youth. Below are the pyramids for the U.S., Montana, and several towns in the region. You can also download a PDF of all pyramids here.