the data user groups that needed such information. For the 1990 census, the Census Bureau undertook even more extensive efforts to improve the geographic basis of its small-area data tabulation programs. Participants in the Block Boundary Suggestion Project could suggest the addition to the Census Bureau’s maps of visible features to be held as 1990 census block boundaries that would permit them to more accurately delimit the voting districts in their States. Another initiative, the 1990 Census Redistricting Data Program, allowed participants to outline their voting districts as groups of whole census blocks so that the Census Bureau could tabulate data for these entities. And finally, the Census Bureau decided to provide data by block throughout the Nation (as well as throughout all the territories). These activities provided State governments with timely small-area population counts for use in Congressional and State legislative redistricting. Chapters 11 and 14 provide further information.
During the past several decades, the Census Bureau has tabulated the results of the decennial censuses of population and housing for several additional kinds of legal and administrative units. These entities include several categories of American Indian and Alaska Native areas, as well as school districts, traffic analysis zones, neighborhoods, and ZIP Codes.
For the 1980 and 1990 censuses, the Census Bureau improved its geographic delineations of American Indian reservations, their subdivisions, and related entities. It also reported more data for the Alaska Native Regional Corporations (ANRCs). For the 1990 census, the Bureau of Indian Affairs (BIA) asked tribal governments to identify their off-reservation tribal and individual trust lands; the Census Bureau designated each area of trust land as one or more separate census blocks.
The Nation’s approximately 16,000 school districts are another kind of administrative area for which the Census Bureau tabulated and presented socioeconomic information from both the 1980 and the 1990 censuses. In this instance, the Census Bureau worked with the U.S. Department of
