About Precinct Types

Election data are available on four different precinct types, coded as RG, RR, SV, and SR precincts. Counties report voter registration on RG precincts, and the Statement of Vote on SV precincts. RG precincts are relatively smaller and more consistent between elections, while SV precincts are larger consolidations of RG precincts, produced for administering a single election. As a general rule, precincts change frequently, and cannot be assumed to have consistent boundaries across elections.

Statewide Database produces RR and SR precincts as adjusted and consolidated versions of county precincts that can be used in redistricting. For redistricting purposes, we merge together precincts that cover the same geographic area, and adjust precinct boundary lines where possible to more closely match the census geography. Our published precinct maps are for these RR and SR precincts.

For data users choosing which precinct type to use, consider:

• Whether you want to visualize election data using our precinct maps. Maps are available for RR and SR precinct data.
• Which the datasets you are interested in. Both Statement of Vote and voter registration data are available on voting precincts (SV and SR), but registration precincts (RG and RR) have smaller geography.
• Whether you are merging Statewide Database data with other outside datasets. Consult the geography and data conversions downloads page to see which data conversions are available for each precinct type.

Statewide Database Diagram

Diagram 1

This diagram illustrates the naming scheme for conversion files in the SWDB. These conversion files are available here.

Definitions:

RG = Original Registration Precincts (designated by County Registrar)

RR = Registration Precincts (geographic unit constructed for statistical merging purposes by SWDB)

SV = Original Voting Precincts (designated by County Registrar)

SR = Consolidated Precinct (geographic unit constructed for statistical merging purposes by SWDB)

1990 City = City Area (designated by US Census Department)

1990 Census Blocks = Census Blocks (designated by US Census Department)

1990 Census Tracts = Census Tracts (designated by US Census Department)

"Cross Election" = moving between election years, i.e. from 1994 geography to 1996 geography

Naming Convention: "origin unit"-"election and year" -"destination unit"_"coverage".CNV

Definitions:

"##" = wildcard symbol

1990 Census Blocks = Census Blocks (designated by US Census Department)

RR = Registration Precincts (geographic unit constructed for statistical merging purposes by SWDB)

Diagram 2

This diagram illustrates the relationship between different types of precincts you may find in our datasets.

These are links to pages explaining "Geographic Hierarchy for the 1990 Decennial Census" and "Small Area Census Geography in the 1990 Census." These pages were drawn from the Geographic Area Reference Manual, Chapter 2, pages 7 and 9. This document is available on the census Web site at www.census.gov.

Overall precinct relationship

The counties have registration (RG) and Voting or consolidated (SV) precincts as well as ballot groups for each election. Registration statistics are reported by RG precinct and election results are reported by SV precinct and/or ballot group (ABSPREC). The counties also report the grouping of RG precincts in SV precinct and Ballot group (although the ballot group reporting is inconsistent and incomplete).

The counties also provide maps or gis files showing registration precinct geography, but the geographic representations do not necessarily match the RG precincts for one or more of the following reasons.

• 1. Zero voter precincts not included in tabular data.
• 2. County has precinct and subprecinct RG precincts and consolidations, but maps don't show subprecinct geography.
• 3. County has alpha-split precincts; Separate RG precincts with common geography, voters separated alphabetically.
• 4. Unexplained inconsistency or incomplete maps.

We create map precincts (MPREC) to reflect the geography as consistently as possible. RR precincts are aggregations of RG precinct (tabular data) into MPRECs (geographic). (Generally speaking Map Precincts are RR precs)

Because the resulting RR precincts may include RG precincts that are consolidated into different SV precincts we create a geographic consolidation know variously as SS or SR precincts to contain whole RR and SV precincts.

Diagram 3 A simple diagram of nesting

The SR precincts are the level at which precinct election results can be given a geographic representation.