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 areas came to outweigh the original criterion of homogeneity. Thus, homogeneity is the primary factor only when preparing a plan for an area that previously did not have census tracts, or when an existing, growing census tract is split into two or more parts.

In accepting or devising a new kind of geographic entity, or in maintaining those that already exist, it is important to keep the geographic concept simple enough, insofar as possible, for ready comprehension and acceptance by all members of the data user community. Easy identification and recognition are key aspects in the wide acceptance of any geographic entity for which the Census Bureau presents data in its tabulations and publications. The identification of most major legal entities is a good example. Despite the fact that these areas are well known to local data users, the Census Bureau shows the names and locations of most governmental units, and displays their boundaries on appropriate maps for the benefit of data users who may be unfamiliar with the territory.

Easy identification is a greater concern for most statistical entities. The naming of statistical entities such as the regions and divisions, UAs, CCDs, and CDPs aids in their recognition by a wide audience. (The same is true of MAs, which are defined by the OMB.) In establishing names for statistical entities, the Census Bureau encourages the use of descriptive terms such as names that are known and already in local use. For several categories of statistical units—census tracts, BNAs, BGs, and census blocks—the large number of entities involved, and the diversity of the area they cover, make it easier and more practical to assign identifying numbers rather than names.

The Census Bureau presents the names or numbers of the statistical entities in its data tabulations, but few people have any concept of the extent or location of the boundaries of Smithbury CDP, much less the location of Census Tract 27. For these reasons, the Census Bureau must provide various types of maps to accompany its data tabulations. Some maps show only the names and general location of the entities in question, but most also show 2-30Geographic Overview