| Resource | Description | Format |
|---|---|---|
| IPUMS-USA | High-precision samples of the American population drawn from federal censuses and the American Community Surveys | .ASCII |
| ICPSR | Census data held by ICPSR | .ASCII |
| data.census.gov | American Community Survey (ACS) Public Use Microdata Samples (PUMS). See tutorials for accessing microdata. | .csv, .sas |
| Census ftp site | PUMS from 1996 to 2015 | .csv |