1990 PUMA Boundary Maps: These maps show the Public Use Microdata Area (PUMA) boundaries for the 1990 state (5%) and metro (1%) samples. In some states, one or more PUMAs include noncontiguous parts. These PUMAs are noted on the maps with "(part)" next to the PUMA number. Noncontiguous PUMAs occur for several reasons. On the metro (1%) sample, every effort was made to keep metropolitan and non-metropolitan areas separate. On 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 which cross state lines appear on the State "99" File, also available on the IPUMS website. Users can locate areas by searching the file under the appropriate MSA/PMSA codes. The elderly (3%) sample has the same geographical components as 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. * The PUMA map of Delaware has never been made available and is missing from the list.1980 PUMA Composition Files: The detailed composition of the PUMA data has been broken down into state-specific tables for both the 1% metro and 5% state samples in the list above. The detailed composition for each PUMA sample is also described in ASCII (compressed) text format in two single files, 1% Sample PUMAs and 5% Sample PUMAs). You will need decompression software to access these files.
