United States County-Specific Net Migration Rates Series

The studies in this series provide county-level net migration estimates for the United States by five-year age cohorts, race, and sex for each decade since 1950. Net migration—the difference between the number of people moving into an area and the number moving out during a given period—is measured in each study in the series using the residual method. That is, net migration is equal to the population change over the period minus the natural increase (births – deaths). Full details on how natural increase is estimated for each county, as well as other aspects of the data collection, are described in the documentation for each study.