The United States Census Bureau defines four statistical regions, with nine divisions.[13] The Census Bureau regions are "widely used...for data collection and analysis".[14] The Census Bureau definition is pervasive.[15][16][17]
Regional divisions used by the United States Census Bureau:[18][19]
- Region 1: Northeast
- Division 1: New England (Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont)
- Division 2: Mid-Atlantic (New Jersey, New York, and Pennsylvania)
- Region 2: Midwest (Prior to June 1984, the Midwest Region was designated as the North Central Region.)[18]
- Division 3: East North Central (Illinois, Indiana, Michigan, Ohio, and Wisconsin)
- Division 4: West North Central (Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, and South Dakota)
- Region 3: South
- Division 5: South Atlantic (Delaware, Florida, Georgia, Maryland, North Carolina, South Carolina, Virginia, Washington D.C., and West Virginia)
- Division 6: East South Central (Alabama, Kentucky, Mississippi, and Tennessee)
- Division 7: West South Central (Arkansas, Louisiana, Oklahoma, and Texas)
- Region 4: West
- Division 8: Mountain (Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming)
- Division 9: Pacific (Alaska, California, Hawaii, Oregon, and Washington)
The current system was introduced for the 1910 census, but other ways of grouping states were used historically by the Census Bureau. The first of these was introduced after the 1850 census by statistician and later census superintendent J. D. B. De Bow. He published a compendium where the states and territories were grouped into five "great division", namely the Middle, New England, the Northwestern, the Southern, and the Southwestern. Unsatisfied with this system, De Bow devised another one four years later, with states and territories grouped into an Eastern, Interior, and Western "great section", each divided into a northern and southern half called "great divisions". In the following decades, several other systems were used, until the current one was introduced in 1910. This system has seen only minor changes: The North region was divided into a Northeast and a North Central region in 1940, Alaska and Hawaii were both added to the Pacific division in the West region upon statehood in 1959, and the North Central region was renamed the Midwest in 1984.[20]