Rural-Urban Commuting Area (RUCA) codes

The concept of rural is complex, multifaceted, and often, vague. In addition, limitations on data availability and the use of different areal units (e.g., counties, census tracts, ZIP code areas, blocks) can create further confusion and disagreement about what kinds of places should be considered “rural.” Because the concept of rural is multidimensional and definitions are tied often to specific views and tasks, no one definition of rural can satisfy all users and purposes. For public policy and research purposes, the definition of rural being applied should be clearly identified and justified. For most public policy purposes, definitions should meet certain criteria, such as being systematic and objective. During the mid-1990s, substantial interest developed among staff at the USDA Economic Research Service (ERS), the Census Bureau, HRSA’s Federal Office of Rural Health Policy (FORHP), and academic demographers and geographers in developing sub-county measures of rural/urban status that would meet those criteria. Those discussions led to a WWAMI RHRC project funded by the FORHP and the ERS that developed the first version of the RUCA codes.

The RUCA codes were designed to provide a definition of rural and urban based on the Census Bureau’s carefully constructed definitions of urbanized areas and urban clusters, which are based on complex criteria including population density and population work commuting patterns. The RUCA taxonomy is based on the size of cities and towns and their functional relationships as measured by work commuting flows. This approach supports the use of the RUCA codes in a wide variety of analytic contexts. The 21 separate codes in the current version (there were originally 33 codes) of the RUCA codes allow demographers, health care researchers, policy makers, and others to aggregate the codes according to their needs. The large number of different codes allows great flexibility in these aggregations. For example, RUCA codes can be used to target a federal health care program to the most appropriate subpopulation. Because the codes are based on census tracts, they are geographically more specific than larger county-based definitions and avoid the problems associated with the heterogeneity of these large units (i.e., problems of under and over bounding the actual boundaries of cities and towns). To make the codes more useful for health care applications, a ZIP code version of the RUCA codes was developed. Older versions of the ZIP code RUCA codes are available on this website and the current version is available from the ERS.

Key References

Hart LG, Larson EH, Lishner, DM. Rural definitions for health policy and research. Am J Public Health. 2005;95(7):1149-1155. Link to Pub Med.

Morrill R, Cromartie J, Hart LG. Metropolitan, urban, and rural commuting areas: toward a better depiction of the U.S. settlement system. Urban Geog. 1999;20(8):727-748.

Acknowledgments

The development of the RUCA codes was supported by HRSA’s Federal Office of Rural Health Policy (FORHP) and the USDA’s Economic Research Service (ERS). The project was led by Drs. Gary Hart (WWAMI RHRC-University of Washington), John Cromartie (ERS) and Richard Morrill (Department of Geography-University of Washington).

Where can CURRENT versions of RUCA codes be obtained?

Where can earlier versions of ZIP code RUCA codes be obtained?

Three versions of the ZIP code RUCA codes are available on this site: http://depts.washington.edu/uwruca/