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What do these census terms mean?

A few examples of Census Bureau terminology are provided below. Visit the full-length Census Glossary for more definitions.

American Factfinder: The Census Bureau’s previous platform for retrieving 2000 and 2010 census data. As of July 2019, American Factfinder was retired and data is now disseminated through data.census.gov.


Ancestry: Refers to a person's self-identification of heritage, ethnic origin, descent, or close identification to an ethnic group. 1980 was the first census which asked about ancestry, previously the census asked about parental place of birth.


American Community Survey: A random survey of 3.5 million households per year, conducted monthly.  1, 3, and 5 year estimates are published by the Census


Block:  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.


Census tract: Designed to be relatively homogeneous units with respect to population characteristics, economic status, and living conditions at the time of establishment, census tracts average about 4,000 inhabitants.


Congressional District (CD): An area established by law for the election of representatives to the United States Congress. Each CD is to be as equal in population to all other CDs in the state as practicable, based on the decennial census counts.


Metropolitan Statistical Area (MSA): A geographic entity based on the concept of a core area with a large population nucleus, plus adjacent communities having a high degree of economic and social integration with that core. Qualification of a metropolitan statistical area requires the presence of an Urbanized Area (UA) with a total population of at least 50,000.


Population estimates: The calculated number of people living in an area as of a specified point in time, usually July 1st. The estimated population is calculated using a component of change model that incorporates information on natural increase (births, deaths) and net migration (net domestic migration, net international migration) that has occurred in an area since the latest decennial census.


Urban Cluster (UC): A densely settled territory that has at least 2,500 people but fewer than 50,000.


Urbanized area (UA): An area consisting of a densely developed territory that contains a minimum residential population of at least 50,000 people.