Allegheny County 2000/2010 Census Tract Relationships

Description

The Allegheny County 2000-2010 Census Tract Relationship File shows how 2010 Census tracts in Allegheny County, Pennsylvania relate to the 2000 Census tracts. Each record (row) consists of one unique relationship between a 2000 Census tract/2010 Census tract spatial set where a spatial set is the unique area shared by the record’s 2000 and 2010 tracts. Changes in tracts involve area, land area, population, and/or housing unit counts. Specifically, each record specifies the area, land area, population, and housing unit counts that were transferred to the record’s 2010 tract (TRACT10) from the record’s 2000 tract. The 2000 area (AREA00), land area (AREALAND00), population (POP00), and housing unit count (HU00) for the record is the standardized 2010 value for the record’s 2000 tract (TRACT00). These are the values to use when comparing 2010 population and housing unit counts to those values in the 2000 Census for a particular tract. The relationship file provides the information necessary to conduct a decennial analysis between the 2000 and 2010 Censuses for a particular tract. Steps to use this file for a decennial analysis follow: 1. Obtain the population and/or housing unit count from the 2000 Census for the tract of interest. 2. Find a record in the relationship file where the tract of interest appears in the TRACT00 field. 3. Compare the population (POP00) and housing unit count (HU00) from the relationship file record to the 2000 Census population and housing unit count found in step 1. This data was prepared by Lisa Over as a course project for LIS 2970 Open Government Data in the Master of Library Science Program at the University of Pittsburgh.

Resources

Name Format Description Link
57 This file contains TIGER shape files for the 2010 tract boundaries for Allegheny County. https://data.wprdc.org/dataset/f7ccd6d1-b38e-4b08-aba1-b78b4e9483ca/resource/adb0d78d-b7bd-459d-93da-a2121d8a3f13/download/tl_2010_42003_tract10.zip
57 This file contains TIGER shape files for the 2000 tract boundaries for Allegheny County. https://data.wprdc.org/dataset/f7ccd6d1-b38e-4b08-aba1-b78b4e9483ca/resource/c2fc7f06-f7f4-4cb1-93fb-fc2a165fd6cf/download/tl_2010_42003_tract00.zip
34 This file is an image of Allegheny County municipal boundaries overlaid with 2010 Census tract boundaries. The purpose of this file is to assist users in finding any tracts or parts of tracts that reside within a particular municipality. The 2010 Census tract boundaries are light blue in color. The municipal boundaries are purple where they coincide with the tract boundaries. The red lines are municipal boundaries that do not coincide with tract boundaries. https://data.wprdc.org/dataset/f7ccd6d1-b38e-4b08-aba1-b78b4e9483ca/resource/ca2cf656-09b2-419f-ad80-251c4aa4035f/download/alleghenymunicipal-2010tracts.png
47 This file contains information about the project and the project files. https://data.wprdc.org/dataset/f7ccd6d1-b38e-4b08-aba1-b78b4e9483ca/resource/3251251b-69b6-4e55-8ebc-ccac53d275b3/download/readme.txt
33 This file includes information about Census tracts and the relationship file. It describes the purpose of Census tracts and how and why tract boundaries change. https://data.wprdc.org/dataset/f7ccd6d1-b38e-4b08-aba1-b78b4e9483ca/resource/2165efd7-701e-4363-84b5-572fbfbe262a/download/about-tracts-and-boundary-changes.pdf
8 This file is a subset of the Pennsylvania relationship file that was retrieved directly from the Census Bureau (pa42trf.txt). This file includes any record where either TRACT00 or TRACT10 in pa42trf.txt was 3, indicating Allegheny County. Tracts are required to follow county lines, however, some of the records had another county specified as TRACT00 with Allegheny County as TRACT10 or vice versa. The 2010 boundary change file for Pennsylvania does not show any boundary changes for Allegheny County. According to Chris Briem, an economist from the University Center for Social and Urban Research (UCSUR), the Census Bureau updated its Pennsylvania geography between the 2000 and 2010 Censuses. The changes in the geography forced adjustments in the tract boundaries, which are reflected in the relationship file. After looking at the 2000 tract and county shape files, he said 2000 tracts line up with 2000 county lines. Likewise, after looking at the 2010 tract and county shape files, he said 2010 tracts line up with 2010 county lines. If working with a 2000 tract (TRACT00) for which the adjustment involved a non-Allegheny County tract, use the POP00 and HU00 values in the same way as with tracts involving only Allegheny County. Allegheny Census tract boundaries changed significantly after the 2000 Census. Chris Briem said that two factors influenced these changes: • The City of Pittsburgh and other areas within Allegheny County had experienced dramatic population declines, and many tracts were merged to accommodate the population requirement. This phenomenon may also be seen in other regions of the country. • The Census Bureau changed how tracts were handled in unpopulated areas. Starting with the 2010 Census, unpopulated areas were divided into tracts separately from populated areas. https://data.wprdc.org/dataset/f7ccd6d1-b38e-4b08-aba1-b78b4e9483ca/resource/bcb6d6a8-8d32-4abb-a377-77d7358d94c2/download/pa_allegheny_42003.csv
8 This file contains information about the fields in the 2000 to 2010 Census Tract Relationship file. https://data.wprdc.org/dataset/f7ccd6d1-b38e-4b08-aba1-b78b4e9483ca/resource/7a27e5b5-da62-43df-9790-00c0d21d88eb/download/data-dictionary.csv
33 This file uses a map and the area of tract 402 to illustrate how each relationship file record corresponds to a unique tract boundary change. Although population is what drives Census tract boundary changes, area lends itself well to visualization, which promotes a more intuitive understanding of the relationships of tracts across Censuses. Changes in area do not always mean population and housing unit counts changed because of the new conventions for unpopulated areas, however, population and/or housing unit count changes necessarily involve a change in area. The boundary lines are dark green where the 2000 tract boundaries coincide with the 2010 tract boundaries. The 2010 Census tract boundaries are light green in color and the 2000 Census tract boundaries are black in color where they differ from each other, indicating tract changes between the two Censuses. The tract numbers displayed are those of the 2010 Census. https://data.wprdc.org/dataset/f7ccd6d1-b38e-4b08-aba1-b78b4e9483ca/resource/e63faf75-a54f-4c4d-a614-2280cf1d9858/download/tract-402-area-changes-illustrated.pdf
34 This file is an image of 2000 Census tract boundaries overlaid with 2010 Census tract boundaries. The purpose of this file is to illustrate the changes to tract boundaries for the 2010 Census. The boundary lines are dark green where the 2000 tract boundaries coincide with the 2010 tract boundaries. The 2010 Census tract boundaries are light green in color and the 2000 Census tract boundaries are black in color where they differ from each other, indicating tract changes between the two Censuses. The tract numbers displayed are those of the 2010 Census. https://data.wprdc.org/dataset/f7ccd6d1-b38e-4b08-aba1-b78b4e9483ca/resource/563c936d-e126-4251-9a4f-9ca61c91c3b3/download/2000-2010tracts.png
23 In this JSON file, Allegheny County 2000/2010 Census Tract Relationship File data is organized by tract. All tracts are included whether from the 2000 Census, 2010 Census, or both. Data for each tract includes the following: • Tract number (referred to below as the ‘main tract’ for distinction from the tracts that have a relationship with this tract) ◦ For each measure - Area, Land Area, Population, and Housing Units - the following is provided ▪ 2010 Value ▪ Standardized Value ▪ Value incorporated into the tract for the 2010 Census; the sum of the quantities equal the 2010 value; the sum of the percentages equal 100% ⁃ Includes each tract number, shared quantity, and percentage of the 2010 value ⁃ This also includes the portion of the main tract that can be considered to have been ‘incorporated into itself from itself’ ▪ Value transferred out of the tract for the 2010 Census; the sum of the quantities equal the standardized 2010 value; the sum of the percentages equal 100% ⁃ Includes each tract number, shared quantity, and percentage of the standardized 2010 value ⁃ This also includes the portion of the main tract that can be considered to have been ‘transferred from itself to itself’ https://data.wprdc.org/dataset/f7ccd6d1-b38e-4b08-aba1-b78b4e9483ca/resource/68a7c778-13ce-44ab-9df0-8e4d647f9d39/download/pa_allegheny_42003.json

Tags

  • allegheny-county
  • council-of-government
  • census
  • allegheny-county-gis

Topics

  • Local Government

Categories