combined statistical area

The United States Office of Management and Budget (OMB) defines micropolitan and metropolitan statistical areas. Metropolitan and micropolitan statistical areas consist of one or more counties (or county-equivalents). Currently defined metropolitan and micropolitan statistical areas are based on application of the 2000 standards (which appeared in the Federal Register on December 27 2000) to Census 2000 data, as updated by application of those standards to more recent Census Bureau population estimates. The current definition is as of December 2006.
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