Public Use Microdata Areas (PUMAs) are geographic areas for which the Census Bureau provides selected extracts of raw data from a small sample of census records that are screened to protect confidentiality. These extracts are referred to as public use microdata sample (PUMS) files. For the 2010 decennial census, each state delineated PUMAs for use in presenting PUMS data based on a 5 percent sample of decennial census or American Community Survey data. These areas are required to contain at least 100,000 people.

The Integrated Public Use Microdata Series (IPUMS-USA) consists of more than fifty high-precision samples of the American population drawn from fifteen federal censuses and from the American Community Surveys of 2000-2009. IPUMS is published and maintained by the Minnesota Population Center, University of Minnesota.

Source of definition:

  • U.S. Census Bureau, Geography Division. Geographic Terms and Concepts – Public Use Microdata Areas

Date of definition: January 2014

Note on IPUMS-USA: For additional information on IPUMS, visit the IPUMS-USA Web site.

Note on 2000 PUMAs and PUMA maps: Through 2011, data by PUMA is presented using the 2000 PUMA regions, that is, the PUMAs that were determined after the 2000 decennial census.

For additional information on the 2000 PUMAs and on the composition of the 2000 PUMAs by state, visit IPUMS-USA’s “Composition of PUMAs and Super-PUMAs” page. The latter page provides links to maps and documents that correlate PUMAs with counties, townships, and Census tracts (especially useful for Chicago).

For a quick view of a correlation of most PUMAs with counties, view a PUMA by county list.

Note on 2010 PUMAs and PUMA maps: Beginning with 2012, data by PUMA is presented using the 2010 PUMA regions, that is, the PUMAs that were determined after the 2010 decennial census.

For a list of which counties and/or which parts of counties are associated with which PUMAs, and for maps of the 2010 PUMAs for Illinois, see the page, 2010 Census Public Use Microdata Area (PUMA) Reference Maps – Illinois, on the U.S. Census Bureau Web site.

Note on data availability by PUMA: PUMAs can be grouped together to match the boundary of a county or a group of counties. IECAM does not report data by PUMA in its search features. Some language data (e.g., specific languages spoken by children age 0-5) are reported by PUMA in the Demographics on Languages in Illinois section of the IECAM Web site. Some data in several categories of Risk Factors for Children and Families in Illinois are reported by PUMA.

Web Resources: Geographic Regions

Related page(s):