Census 2010. The decennial census has traditionally started in the fall of the year '04 preceeding the decennial census. By way of Federal Register announcement of the 2010 Census Redistricting Data Program, the Census Bureau commences preparation for Census 2010.
The Census 2000 Data Access and Use web pages augment the information on Census 2000 provided by the Census Bureau by adding other types of information, news, and perspectives focused on data access and use.
Focus of the Census 2000 Data Access and Use web pages is on:
Title 13 of the U.S. Code requires that the apportionment counts--the resident population totals for each state--be delivered to the President within 9 months of the census date. In the 1990 and most 20th Century censuses, the census date has been April 1, meaning that the Office of the President received the counts by December 31 of each census year. Within a week of the opening of the next session of the Congress, the President must report to the Clerk of the House of Representatives the census counts for each state and the number of Representatives to which each jurisdiction is entitled. Within 15 days, the Clerk of the House informs each state Governor of the number of Representatives to which each state is entitled. The legislatures in each state are responsible for geographically defining the boundaries of their congressional and other election districts--the redistricting process which requires more detailed census data.
Public Law 94-171, which amended the Census Law (Title 13, U.S. Code), was enacted by Congress in 1975, and guides the Census 2000 redistricting data program. The purpose of this law is to provide state legislatures with small-area census population totals for legislative redistricting. However, there is a broader interest in the P.L. 94-171 data products that extends beyond the stated purpose of the law due to (1) the use of these data in other types of apportionment and redistricting and (2) these data being the first data to become available from the Census. More information is available on the Census Internet site.
Implications of Census 2000 Data and Reapportionment
Article 1, Section 2, of the United States Constitution states:
"Representatives and direct Taxes shall be apportioned among the several States which may be included within this Union, according to their respective Numbers...The actual Enumeration shall be made within three Years after the first Meeting of the Congress of the United States, and within every subsequent Term of ten Years, in such Manner as they shall by Law direct."
Therein lies the primary mandate of the U.S. census, apportionment of the House of Representatives. Since that first census in 1790, five methods of apportionment have been used. The current method used, the Method of Equal Proportions, was adopted in 1941 following the census of 1940. This method assigns seats in the House of Representatives according to a "priority" value. The priority value is determined by multiplying the population of a State by a "multiplier." For example, following the 1990 census, each of the 50 states was given one seat out of the current total of 435. The next, or 51st seat, went to the State with the highest priority value and thus became that State's second seat. This continued until all 435 seats had been assigned to a state.
To view the mechanical aspects of this process, you may look at the spreadsheet that enables you to see state-by-state how additional seats are assigned.
Census 2000 Data and Redistricting More Generally. While the foregoing description of the role of Census 2000 in Congressional reapportionment and redistricting, Census 2000 data will be widely used in other types of redistricting applications. These redistricting applications include redistricting state legislatures, other types of statewide geographic area redistrictings, marketing and service areas, school districts (attendance areas and election areas), police beats, fire districts, environmental-related management areas, city election districts, and other types of geography. See Redistricting Resources and Operations for more information about redistricting software, data, processes, and applications.