Which demographic variable refers to the movement of people into or out of a region?

• A. Fertility
• B. Mortality
• C. Net migration
• D. Age structure

Answer: (C)

Net migration is the movement of people into or out of a region. It specifically tracks how population size changes due to relocation, considering both in-migrants and out-migrants. If more people move in than out, the region experiences positive net migration and gains residents; if more leave than arrive, it’s negative and the region loses residents. This makes it the term that directly captures geographic movement. In contrast, fertility refers to birth rates, mortality to death rates, and age structure describes how the population is distributed across age groups, not movement itself. Net migration can also influence other demographic features indirectly, but its defining feature is the balance of people coming and going.