A Combined Statistical Area (CSA) as defined by the U.S. Census Bureau is a aggregation of adjacent metropolitan and micropolitan statistical areas that are economically and socially interconnected. CSAs are used for providing a more comprehensive view of the larger regions in which residents live and work, transcending administrative boundaries to better illustrate the multi-faceted nature of these urban clusters.
A Metropolitan Statistical Area (MSA) includes one or more counties with a central urban area having a population of at least 50,000 inhabitants. The U.S. Census Bureau uses MSAs for the purposes of aggregating and reporting population, housing, and economic statistics.
The designated city within a Metropolitan Statistical Area (MSA) or Micropolitan Statistical Area (µSA) that serves as the primary city or city center. This designation is used for demographic, economic, and planning purposes.
