Bureau of the Census April 6, 2007 – Federal Register Recent Federal Regulation Documents

Block groups are statistical geographic divisions of a census tract, defined for the tabulation and dissemination of decennial census data. Block groups also will be used to tabulate and publish estimates from the American Community Survey (ACS) \1\ after 2010. Each block group comprises a reasonably compact and contiguous cluster of census blocks; up to nine block groups can be contained within a single census tract.

Census designated places (CDPs) \1\ are statistical geographic entities representing closely settled, unincorporated communities that are locally recognized and identified by name. They are the statistical equivalents of incorporated places, with the primary differences being the lack of both a legally defined boundary and an active, functioning governmental structure, chartered by the state and administered by elected officials. CDPs defined for the 2010 Census also will be used to tabulate American Community Survey, Puerto Rico Community Survey, and Economic Census data after 2010, and potentially data from other Bureau of the Census (Census Bureau) censuses and surveys.