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Resident population and net change

Source: U.S. Bureau of the Census, Population Estimates Program (PEP). Updated annually. http://www.census.gov/population/www/estimates/popest.html

Estimates are made for the United States, areas within the United States, and Puerto Rico. The frequency of estimates and availability of demographic detail vary by geographic level. The schedule of releases are available at http://www.census.gov/population/www/estimates/estsched.html.


The Census Bureau's Population Estimates Program (PEP) produces July 1 estimates for years after the last published decennial census (1990), as well as for past decades. Existing data series such as births, deaths, Federal tax returns, medicare enrollment, and immigration, are used to update the decennial census base counts. PEP estimates are used in Federal funding allocations, in setting the levels of national surveys, and in monitoring recent demographic changes. A methodology reference accompanies most of our population estimates offerings.

With each new issue of July 1 estimates, PEP revises estimates for years back to the last census. Previously released estimates become superseded. Revisions to estimates are usually due to input data updates, changes in methodology, or legal boundary changes.

Scope and Methodology:

County population estimates are created by starting with the most recent decennial census figure (April 1, 1990) and updating that figure with information on births, deaths, domestic migration (in/out flows with other counties in the U.S.), and international migration (in/out flows with other countries) that have taken place between the census date and the date of the population estimate. Birth and death data are obtained through vital statistics, domestic migration is estimated through the address matching of federal tax returns, and international migration data is supplied by the Immigration and Naturalization Service.

More information:

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