Census and Census Bureau

A state's apportionment population is the sum of its resident population and a count of overseas U.S. military and federal civilian employees (and their dependents living with them) allocated to the state, as reported by the employing federal agencies.

The Constitution provides for an enumeration of the population to serve as the basis for the apportionment of members of the U.S. House of Representatives among the states, with the provision that each state must have at least one representative.