Redistricting Data

Data

2010 Census Data and Resources

2010 Census [P.L. 94-171] Summary Files

The 2010 Census Redistricting Data [P.L. 94-171] Summary Files were posted, by state, from February 3rd through March 24th of 2011. The summary file tables contain tabulations for:

• Table P1 - Race
• Table P2 - Hispanic or Latino, and not Hispanic or Latino by Race
• Table P3 - Race for the Population18 Years and Over
• Table P4 - Hispanic or Latino, and not Hispanic or Latino by Race for the Population 18 Years and Over
• Table H1 - Occupancy Status (Housing)

The Tech Tips page of this website contains many resources to assist data users when working with the [P.L. 94-171] Summary Files including: Microsoft Access database shells with instructions, SAS database shells, and guidance on constructing a GEOID for joining data to TIGER/Line shapefiles.

The 2010 Census Redistricting Data [P.L. 94-171] Summary File Technical Documentation is now available in English P.L. 94-171 Technical Documentation [PDF 3.75 MB] and in Spanish (for Puerto Rico) P.L. 94-171 Technical Documentation- Spanish [PDF 3.82 MB]

The 2010 Census Redistricting Data [P.L. 94-171] Summary File data are available for all 50 states, the District of Columbia, and Puerto Rico through the American FactFinder and via FTP download. Due to session constraints in American FactFinder, users who want to download all blocks within a state should use the FTP site for their files.

2010 Census Geographic Support Products

TIGER/Line shapefiles

All 50 states, the District of Columbia, and Puerto Rico are available for download from the U.S. Census Bureau's 2010 TIGER/Line products web page.TIGER/Line Shapefiles

The technical documentation for the 2010 Census Redistricting [P.L. 94-171] TIGER/Line Shapefiles can be accessed here:

• 2010 Census Redistricting [P.L. 94-171] TIGER/Line Shapefile Technical Documentation

TIGERweb

TIGERweb: A new tool from the Census Bureau's Geography Division that allows users to visualize the 2010 census geography. This tool includes legal and statistical areas with their geographic identifiers, as well as the transportation network, and hydrography layers in the TIGER database. In addition, it contains the 2010 Census population and housing unit counts for the various geographic entities.

• TIGERweb Home Page
• TIGERweb is also available as a Web Mapping Service (WMS) using http://tigerweb.geo.census.gov/ArcGIS/services/tigerWMS/MapServer/WMSServer

2010 Census Redistricting Maps

The 2010 Census Redistricting Maps are available for all 50 states, the District of Columbia, and the Commonwealth of Puerto Rico.

• 2010 Census [P.L. 94-171] Voting District/State Legislative District Reference Maps
• 2010 Census [P.L. 94-171] County Block Maps
• 2010 Census Tract Reference Maps
• 2010 Census School District Reference Maps

2010 Census Block Assignment Files

The 2010 Census Block Assignment Files and Name Look-up tables are intended for data users who want to know which blocks make up a specific geography and/or those who wish to use the demographic data without using the TIGER/Line shapefiles. The Block Assignment Files are being generated for the following geographies:

• Congressional Districts
• State Legislative Districts
• Voting Districts
• School Districts
  • Elementary
  • Secondary
  • Unified
• Incorporated Places + Census Designated Places
• American Indian/Alaska Native/Hawaiian Homeland Areas

There is one Name Look-up table generated for each level of geography with the exception of the Incorporated Place + Census Defined Place table. For that geography there are two Name Look-up tables generated, one for Incorporated Places and another for Census Defined Places.

2010 Census Block Relationship Files

The U.S. Census Bureau's Geography Division has produced 2010 Census Block Relationship Files which include crosswalk files, by state, between Census 2000 tabulation blocks and 2010 Census tabulation blocks. These files are available on the 2010 Block Relationship File web page.

2010 Census Tract Relationship Files

The U.S. Census Bureau's Geography Division has produced 2010 Census Tract Relationship Files which include crosswalk files, by state, between Census 2000 Census Tracts and 2010 Census Tracts. These files are available on the 2010 Tract Relationship File web page.

2010 Census Block Counts

A table showing the number of Census 2000 blocks, Census 2010 blocks, and the change in number between the two decennials. Tallies of Census Blocks by State or State Equivalent.

Additional 2010 Census Resources

2010 Census Advance Group Quarters File

The Census Bureau, in response to Federal officials, state officials, and other data users, provided an early version of Table P-42 from the 2010 Census Summary File 1, showing the seven types of group quarters. No characteristics of the group quarters were provided. The institutionalized group quarters categories include correctional facilities for adults, juvenile facilities, nursing facilities/skilled-nursing facilities and other institutional facilities; while the non-institutionalized group quarters categories include college/university student housing, military quarters and other non-institutional facilities. Data are provided for states, counties, census tracts and blocks. This table is only available via FTP, so will not be found in the American Fact Finder.

This early release of data on the group quarters population was beneficial to many data users including those in the redistricting community who must consider whether to include or exclude certain populations in redrawing boundaries as a result of state legislation. It permitted state and local redistricting officials to overlay this file with the 2010 Census Redistricting Data (Public Law 94-171) Summary File data. Three states (Delaware, Maryland and New York) have legislation requiring use of group quarters data in their line drawing. Other states exclude military, and Kansas reassigns intrastate college students back to their home town.

In addition, this product may be useful in determining if a geocoding error has occurred. The Count Question Resolution (CQR) Program provides state, local, and tribal governments the opportunity to challenge their 2010 Census housing unit and group quarters counts. The CQR program began June 1, 2011, prior to the release of the Summary File 1.

2010 Census Advance Group Quarters Summary File Technical Documentation [PDF 4.85 MB]

2010 Census Advance Group Quarters Summary File FTP Data

2010 Census Advance Group Quarters Microsoft Access Shells -- These shells (MS Access 2007 and MS Access 2003 versions) contain the file import specifications, example tables, an example block level query, and a brief data dictionary extract, to assist you with importing and extracting the data. These shells are used similarly to the ones in the instructions titled How to use Access Shells [PDF 880 KB]

Count Question Resolution Program

The Census Bureau established the 2010 Census Count Question Resolution (CQR) Program by which State, local and Tribal area elected officials may challenge their jurisdiction's 2010 Census counts. On June 1, 2011, the Count Question Resolution (CQR) Program began accepting 2010 Census challenge submissions. All challenges must be received by the Census Bureau no later than June 1, 2013.

Other 2010 Census Summary Files

Demographic Profiles FTP AFF

Summary File 1 Technical Documentation [PDF] FTP AFF

Summary File 2 Technical Documentation [PDF] FTP AFF

Redistricting Prototype Data from the 2008 Dress Rehearsal

On March 30, 2009, the Census Bureau's Redistricting Data Office released the 2008 Redistricting Data Prototype (Public Law (P.L.) 94-171). Released two years in advance of the 2010 Census Redistricting Data, the prototype was designed to provide states, the Department of Justice, vendors, and other stakeholders the opportunity to build their redistricting systems in preparation for the redistricting of congressional and state legislative district boundaries in 2011.

The prototype contains two discs:

1. The 2008 Redistricting Data Prototype (P.L. 94-171) Summary Files illustrate the proposed format and content of the redistricting data, including four population tables and one housing unit table down to the census block level.
2. The 2008 Redistricting Data Prototype (P.L. 94-171) Geographic Products illustrate the proposed format and content of the geographic data, including congressional districts, state legislative districts, voting districts, census tracts and census blocks. The following maps in PDF format are available as well: County Block Maps, Voting District/State Legislative District Reference Maps, Census Tract Reference Maps, and School District Reference Maps.

Both the data and geography reflect information for San Joaquin County, California.

The P.L. Summary file extraction software has been reported to not function on certain Windows configurations. Should you encounter this problem, please use the following link for instructions and files to update the extraction software. This update also includes a 64 bit computer compatibility update.
Redistricting Data Prototype (P.L. 94-171) Summary File Extraction Software Update

Please call the Census Redistricting Data Office at (301) 763-4039 should you have any questions.