A statistical area bounded by visible features, such as streets, roads, streams, and railroad tracts, and by nonvisible boundaries, such as selected property lines and city, township, school districts, and county limits.
A block is the smallest geographic unit for which the Census Bureau tabulates 100-percent data.
Many blocks correspond to individual city blocks bounded by streets, but blocks – especially in rural areas – may include many square miles and may have some boundaries that are not streets. The Census Bureau established blocks covering the entire nation for the first time in 1990. Previous censuses back to 1940 had blocks established only for part of the nation. Over 8 million blocks were identified for Census 2000 and over 11 million blocks are identified for the 2010 Census.
Related terms: Block
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