Sources: U.S. Census Bureau, Population Estimates Program (PEP), updated annually. Population and Housing Unit Estimates
The Census Bureau's Population Estimates Program (PEP) produces estimates of the population for the United States, its states, counties, cities, and towns, as well as for the Commonwealth of Puerto Rico and its municipios (county-equivalents for Puerto Rico). Additionally, housing unit estimates are produced for the nation, states, and counties. The timing of the release of estimates varies according to the level of geography. See the Schedule of Releases for more information.
Resident Population - All persons who are "usually resident" in a specified geographic area. For the United States, the resident population includes all persons who usually reside in the 50 states and the District of Columbia, but excludes residents of the Commonwealth of Puerto Rico and the Island areas under U.S. sovereignty or jurisdiction (principally American Samoa, Guam, United States Virgin Islands, and the Commonwealth of the Northern Mariana Islands). In addition, the U.S. resident population excludes U.S. Armed Forces overseas and civilian U.S. citizens whose usual place of residence is outside the United States.
Estimates Base - The population count or estimate used as the starting point in the estimates process, and which typically corresponds with the date of the latest decennial census. The April 1, 2020 Population Estimates base may reflects changes to the 2020 Census population from the Boundary and Annexation Survey (BAS) and other geographic program revisions, the application of disclosure avoidance techniques, or the incorporation of alternate data sources. Click on the "Scope and Methodology" link for details for each vintage year.
Population percent change - The difference between the population of an area at the beginning and end of a time period, expressed as a percentage of the beginning population.
Methodology for U.S. and Puerto Rico