Chapter 6
Statistical Groupings of States and Counties
Users of Census Bureau data find it advantageous to relate these data to geographic entities that represent major sections of the United States. These geographic regions usually comprise combinations of States or counties. Such groupings are particularly appropriate for a large nation such as the United States, with its diverse physical and cultural geography, and its numerous State and county components.
This chapter discusses the Census Bureau’s system of State groupings, the Census Bureau’s regions and divisions, as well as other combinations based on groupings of contiguous counties. Figure 6-1 shows the Census Bureau’s current two-level system for the regional subdivision of the United States. Each of the current nine census divisions consists of several States (including the District of Columbia, located in the South Atlantic Division); each of the four current census regions consists of two or three divisions (the Midwest Region was designated as the North Central Region until June 1984). At both the region and division level, the framework of areas provides complete coverage of the entire Nation. The purpose of this framework is to provide large units that are roughly similar in terms of historical development, population characteristics, economy, and the like. As a result, the regions and divisions serve not only to summarize data for the same groups of States over a long period of time, but also to provide a larger geographic framework for comparative statistical analysis.
The current regions and divisions have been standard data tabulation units in almost all Census Bureau tabulation and publication programs since the early 1900s. They appear in many summary tables of the decennial censuses of population and housing, in the publications of the economic and agriculture censuses, and in other statistical presentations, not only those of the Census Bureau, but also of other Federal agencies and private groups. The Census Bureau has no official summary units, other than the regions and divisions, that combine all the Nation’s counties and statistically equivalent entities into a more concise set of general-purpose areas.
Statistical Groupings6-1
