Data Sources:

• U.S. Census Bureau, American Community Survey, 2010
• U.S. Census Bureau, Decennial Census, 2010
• Internal Revenue Service, Net Migration Flows, by County, 2000–2009  

For more information about sources

Definitions:

• Metropolitan Statistical Area (MSA): A group of counties that includes a Census Bureau-defined urbanized area of at least 50,000 inhabitants and a total metropolitan population of at least 100,000. The county that contains the largest city becomes the “central county.” Additional “outlying counties” are included in the MSA if they meet specified requirements of commuting to the central county and other selected requirements of metropolitan character (such as population density and percent urban).
• Migration: The movement of population in and out of a defined geographic area. Net migration is calculated by subtracting out-migrants from in-migrants. Net migration along with net natural population increase (births minus deaths) are the components of population change.

Update Status:

Updated October 2011