2003 Redistricting Reference Data

Overview

A large amount of reference data is needed to draw political districts. This data can be divided into two main groups: numeric and geographic. The numeric component includes items such as population and voter registration values. The geographic component includes features such as roads, rivers, and political boundaries that can be graphically displayed as features on a map.

The numeric data matches up with the geographic data at several different levels. The main levels of interest in district drawing are counties, voter precincts, and census blocks. These three main levels have a nesting relationship. In other words, counties are comprised of voter precincts that, in turn, are comprised of census blocks. Each level covers the entire territory of the state, such that there is no point within the state's boundaries that cannot be assigned to each of the three levels.

All information on this page corresponds with the redistricting database compiled by the General Assembly in October of 2003.

  • *Voter Registration and Election reports are not provided at the municipal level because the underlying data comes to us based on precinct geography, which often has no inherent relationship with municipal geography.

There were three main types of numeric data in the 2003 redistricting database:

Population Data - by April 1st of the year following each decennial census, the US Census Bureau provides Public Law 94-171 data to each of the states. This data corresponds with block level geography, the lowest level tabulated by the Census Bureau, and that at which districts are ultimately defined. The Public Law 94-171 data contains only race and ethnicity breakdowns of total and voting age populations.

Voter Registration Data - the State Board of Elections provided registration information for all voter precincts in the state as recorded in their State Elections Information Management System (SEIMS). In this data set, vintage December 2002, registered voters are broken down by party, race, gender, and age group.

Election Returns Data - also provided by the State Board of Elections at the voter precinct level, information is included for various contests from the 2000 and 2002 general elections. Note that county boards of elections were not required to report all votes at the precinct level. Each county has a county-wide "absentee/provisional" category. Since inclusion of these figures would tend to homogenize the precinct-level results, they were excluded from the database. Data on three non-statewide elections were included - US House, NC House, and NC Senate. Statewide redistricting requires that all data items be available statewide. For these contests, votes were therefore tabulated by party rather than by candidate and district.

Complete datasets, as processed for use in the General Assembly's redistricting system, are linked below for download. The field layout definition is required to interpret the information. Also included is a "block level units key" which is useful for establishing relationships between the different geographic levels. Note that although registration and elections data are available at all levels for system consistency, they are most reliable at the precinct and county levels since the original data was precinct-based.

The geographic data in the General Assembly's 2003 redistricting system was based on the "Urban Area Census 2000" TIGER/Line Files provided by the US Census Bureau. Below are links to various statewide layers extracted from that dataset. The voter precinct layer, though originally derived from 2000 TIGER, was updated to reflect precinct changes through the October 2003 redistricting database build.

These datasets are intended for use with geographic information system (GIS) software. Layers are in shapefile format. The shapefiles are projected in the North Carolina State Plane coordinate system. Units are in meters. Due to their relatively large sizes, and the fact that each "shapefile" consists of a group of files, all layers have been compressed.

Shapefile. This is a spatial data format created by ESRI. Each "shapefile" is actually a collection of several files, each with the same name, but a different file extension. These files are used with geographic information system (GIS) software.

Tab-Delimited Text (*.tab) is a simple text format consisting of values separated by tabs. It is easily imported into spreadsheet and database programs, with each line of the file corresponding to a table row, and each item in a line corresponding to a table column. It can also be viewed with text editor programs such as NotePad or WordPad, provided the file isn't too large.

ZIP. Due to large size, some of the files linked from this site have been compressed or "zipped". In addition to native support in some operating systems, a variety of commercial and open source programs exist that can extract ".zip" files.