DESCRIPTION OF CODES AND TECHNICAL NOTES
Rural-Urban Commuting Areas
(For Residential & Commercial/Geographic Zip Codes: Version 1.1)
This is a text tab-deliminated file with five variables as follows:
Column 1 = zip code: alpha version
Column 2 = zip code: numeric version
Column 3 = RUCA Code
Column 4 = Population Category
Column 5 = State Code
Tech Notes:
- There are 42,326 total cases. This includes both residential/geographic and PO Box commercial zip codes.
- The population categories are defined as follows:
1: 0-99
2: 100-499
3: 500-999
4: 1000 or more - The state code used is the FIPS state.
- There are 6 zip codes that overlap state boundaries:
ZIP 42223: Kentucky/Tennessee overlap
ZIP 57724: Montana/South Dakota overlap
ZIP 63673: Illinois/Missouri overlap
ZIP 71749: Arkansas/Lousiana overlap
ZIP 72395: Arkansas/Tennessee overlap
ZIP 73949: Oklahoma/Texas overlap - To address this problem, each of these zips appear TWICE—once in each state in which it appears. A decimal designation is attached to each of these zips so that the portion of the zip having the larger population is shown as xxxxx.1 and the portion having the smaller population as xxxxx.2.
- This has ramifications for national-level analyses as well as for the overall count of zip codes. Precautions must be taken in order not to double count these 6 zip codes at the national level.
(RUCAs)
These RUCA codes for zip level analysis are derived from the census tract level RUCA codes and the definitions given below apply.
Census tracts are assigned to categories based on commuting data and Census Bureau definitions (e.g., urbanized area and urban place are Census Bureau terms with specific definitions).
1. Urban core Census tract
[primary flow within Census Bureau defined Urbanized Area (metro>= 50,000)]
1.1 secondary flow (30-50%) to larger urbanized area
1.0 otherwise
2. Census tract strongly tied to urban core
[primary flow to Census Bureau defined Urbanized Area (>30%)]
2.1 secondary flow (30-50%) to larger urbanized area)
2.2 combined flows to urbanized areas of >30% and greater than primary flow
2.0 otherwise
3. Census tract weakly tied to urban core
[primary flow to Census Bureau defined Urbanized Area but 5-30%]
3.0 --
4. Large town Census tract
[primary flow within large Census Bureau defined Urban Place (10,000-49,999 & >30%)]
4.1 secondary flow (30-50%) to urbanized area
4.0 otherwise
5. Census tract strongly tied to large town
[primary flow to large Census Bureau defined Urban Place (>30%)]
5.1 secondary flow (30-50%) to urbanized area
5.0 otherwise
6. Census tract weakly tied to large town
[primary flow to large Census Bureau defined Urban Place (5-30%)]
6.0 --
7. Small town Census tract
[primary flow within small Census Bureau defined Urban Place (>= 2,500 & <10,000 & >30%)]
7.1 secondary flow (30-50%) to urbanized area
7.2 secondary flow (30-50%) to large urban place
7.3 secondary flow (5-30%) to urbanized area
7.4 secondary flow (5-30%) to large urban place
7.0 otherwise
8. Census tract strongly tied to small town
[primary flow to a small Census Bureau defined Urban Place (>30%)]
8.1 secondary flow (30-50%) to urbanized area
8.2 secondary flow (30-50%) to large urban place
8.3 secondary flow (5-30%) to urbanized area
8.4 secondary flow (5-30%) to large urban place
8.0 otherwise
9. Census tract weakly tied to small town
[primary flow to a small Census Bureau defined Urban Place (5-30%)]
9.1 secondary flow (5-30%) to urbanized area
9.2 secondary flow (5-30%) to large urban place
9.0 otherwise
10. Isolated small rural Census tract (remaining rural tracts)
[no primary flows over 5% to any Census Bureau defined Urbanized Area (metro), large Urban Place, or small Urban Place]
10.1 secondary flow (30-50%) to urbanized area
10.2 secondary flow (30-50%) to large urban place
10.3 secondary flow (30-50%) to small urban place
10.4 secondary flow (5-30%) to urbanized area
10.5 secondary flow (5-30%) to large urban place
10.0 otherwise