1990 PUMA Definitions
The table below provides links to maps and composition files for the Public Use Microdata Areas (PUMAs) identified in the 1990 state (5%) and metro (1%) samples.
In some states, one or more PUMAs include noncontiguous parts. These parts are identified on the maps by a PUMA number followed by "(part)". Noncontiguous PUMAs occur for several reasons. For the metro (1%) sample, every effort was made to keep metropolitan and non-metropolitan areas separate. For the state (5%) sample, it was important to keep meaningful socioeconomic or planning areas together. In sparsely populated areas, it may have been necessary to delineate PUMAs with noncontiguous parts to meet minimum population criteria when the adjacent counties belonged to either a metropolitan area or local planning area.
PUMAs in the elderly (3%) sample have the same geographical components as in the state (5%) sample. The Census Bureau equated the State Planning Service Areas (PSAs) to the state PUMAs whenever the two were equal. If the two were not equal, the PSA code is 000.
1990 PUMA Maps and Composition Files by State
* The PUMA map of Delaware has never been made available.
All boundary files are provided as shapefiles within .ZIP files.