How do population pyramids reflect a country's demographic structure?

• A. They show population density by region.
• B. They show age and sex composition; wide bases indicate young populations; top-heavy indicate aging.
• C. They show GDP by age group.
• D. They show literacy by gender.

Answer: (B)

Population pyramids reveal the age and sex structure of a country’s population. Each horizontal bar shows how many people are in a given age group, split by sex, so you can see the balance between younger and older cohorts. A broad base means many young people, indicating high birth rates and potential for rapid population growth. A shape that widens toward the top signals an aging population, with relatively more older adults and often lower birth rates. Because the chart shows both age and sex, you can also note sex ratios at different ages and how they shift as people age. In short, the pyramid’s overall silhouette—youthful, uniform, or aging—encodes a country’s demographic structure and its likely future trends.