Metropolitan statistical area
A metropolitan statistical area (MSA) is a geographical region in the United States that has a relatively high population density at its centre and tight economic linkages across the whole area. The term "MSA" is an abbreviation for "metropolitan statistical area." Due to the fact that such areas are not legally established in the same way that a city or town would be, nor are they formal administrative divisions like counties, nor are they independent entities like states, the specific definition of any particular metropolitan area might vary depending on the source. In 1949, the statistical requirements for what would come to be known as a standard metropolitan area were established, and in 1983, those same criteria were renamed "metropolitan statistical area."
The primary focus of a typical metropolitan area is on a single sizable metropolis that exerts a significant level of control over the surrounding area (e.g., New York City or Chicago). The Dallas–Fort Worth metroplex, the Virginia Beach–Norfolk–Newport News (Hampton Roads) metropolitan area, the Riverside–San Bernardino (Inland Empire) metropolitan area, and the Minneapolis–Saint Paul (Twin Cities) metropolitan area are some examples of metropolitan areas that contain more than one large city but no single municipality holds a substantially dominant position. The United States Office of Management and Budget (OMB) is responsible for defining MSAs, which are then used for statistical reasons by the United States Census Bureau and other federal government departments.
The Office of Management and Budget of the United States of America establishes a number of core based statistical areas (CBSAs) around the nation. These CBSAs are made up of counties and county equivalents. The boundaries of CBSAs are determined by a core, continuous region that has a relatively high population density. This region is referred to as an urban area or urban cluster. The counties that comprise the core urban area are known as the central counties of the CBSA. These counties are characterised as having at least fifty percent of their population residing in urban regions that have a population of at least ten thousand people. The Central Business Service Area (CBSA) can expand to include additional surrounding counties, which are referred to as outlying counties, if these counties have strong social and economic ties to the county or counties that make up the CBSA. These ties can be measured by commuting patterns and employment rates. The Central Business Service Area (CBSA) includes outlying counties if either 25% of the people who reside in those counties hold jobs in the core county or counties, or if 25% of the jobs held in those counties are held by people who live in the central county or counties.
Adjacent When a CBSA's core county or counties qualify as an outlying county or counties to other CBSAs, the CBSA in question is combined with the other CBSAs to form a single CBSA. When the employment interchange measure (EIM) reaches 15% or more, one or more CBSAs may be merged together or combined to create a bigger statistical entity known as a combined statistical area (CSA). This larger entity is known as a combined statistical area (CSA).
CBSAs can be further subdivided into metropolitan statistical areas (MSAs), which are built around urban clusters with a population of at least 50,000 people, and micropolitan statistical areas (SAs), which are CBSAs built around an urban cluster with a population of at least 10,000 people but less than 50,000 people. In some metropolitan regions, there may be many cities that individually have less than 50,000 inhabitants but, when added together, have more than 50,000 people. Standard metropolitan statistical area (SMSA) and principal metropolitan statistical area are two phrases from the past that are no longer in use (PMSA).
On January 19, 2021, the Office of Management and Budget (OMB) proposed a rule for public comment that would raise the minimum population required for an urban area population to be considered a metropolitan statistical area from 50,000 to 100,000 people. This change would take effect in 2022. In the end, they came to the conclusion that the minimum should remain at 50,000 for the 2020 cycle.