Centre County, Pennsylvania
The United States Office of Management and Budget has designated Centre County as the State College, PA Metropolitan Statistical Area (MSA). As of the 2010 U.S. Census the metropolitan area ranked 13th most populous in the State of Pennsylvania and the 259th most populous in the United States with a population of 155,403. Centre County is also a part of the larger State College-DuBois, PA Combined Statistical Area (CSA), which combines the populations of Centre County as well as Clearfield County to the west. The Combined Statistical Area ranked 9th in the State of Pennsylvania and 123rd most populous in the United States with a population of 236,577.
Metropolitan statistical area
The U.S. Office of Management and Budget defines a set of core based statistical areas (CBSAs) throughout the country. CBSAs are delineated on the basis of a central urban area or urban clusterin other words: a contiguous area of relatively high population density. CBSAs are composed of counties and county equivalents. The counties containing the core urban area are known as the "central counties" of the CBSA. A central county is a county in which 50% of its population lives in urban areas of at least 10,000 in population, or where a population of 5,000 are located in a single urban area of at least 10,000 in population where that urban area is split between more than one county. Additional surrounding counties, known as "outlying counties", can be included in the CBSA if these counties have strong social and economic ties to the central counties as measured by commuting and employment. Outlying counties are included in the CBSA if the employment interchange measure (total of in- and out-commuting) is 25% or more, although these numbers are estimates and exceptions are made. Some areas within these outlying counties may be rural in nature. All counties in a CBSA must be contiguous, and a county can only be included within one CBSA. In New England, towns have precedence over counties, so statistically similar areas are defined in terms of town-based units known as New England city and town areas (NECTAs).