For 1980, the census block program expanded once again to include, in addition to urbanized areas, all incorporated places of 10,000 or greater population. Selection of these places was based either on the 1970 population count, an official Census Bureau estimate published in 1973, 1975, or 1976, or a special census conducted before December 31, 1977. Also, States and local agencies continued to contract with the Census Bureau for census block data for additional areas. For the 1980 census, five States (Georgia, Mississippi, New York, Rhode Island, and Virginia) contracted with the Census Bureau to provide census block statistics for their entire area and population. The Census Bureau published selected data for over 2.5 million census blocks (an increase of 900,000 over 1970) and 154,456 BGs. Census block coverage included approximately 78 percent of the Nation’s population and 7 percent of its land area. In cases where the extension involved only limited additional territory, the Census Bureau extended the census block coverage from the potential urbanized area to include the entire area of the county in which the potential urbanized area was located.
In its 1980 data products, the Census Bureau again published statistics for tabulated blocks by SMSA. It also produced a Selected Areas report for each State to cover all census blocks outside of metropolitan areas. For the first time, the maps were published separately from the reports. The Census Bureau’s Summary Tape File (STF) 1B included data for census blocks and BGs. Both the published reports and the STF 1B included a special table that listed census blocks with no population and housing.
Following the 1980 census, the Census Bureau made a major commitment to develop a geographic data base that would provide better data tabulations and presentations for the entire Nation, Puerto Rico, and the Outlying Areas. Historically, the delivery of geographic materials and services at the Census Bureau involved a series of complex and functionally separate
Census Blocks and Block Groups11-7
