View the available subjects, detailed codes for variables, changes related to each release, an explanation of sample design, methodology, and accuracy, and files to determine if you are using weights correctly for the American Community Survey Public Use Microdata Sample (PUMS) files. These documents are organized by data year.
Supporting data for the documentation below is available on the Accessing PUMS Data page.
Guidance for novice ACS PUMS files users.
Important information about 2021 geography and variable changes.
A list of topics included in each of the housing and population record files.
Detailed codes for variables that contain a large number of coded responses, such as ancestry and occupation.
Includes variables available for each release of PUMS files on the Census Bureau FTP site, and how each variable is coded.
Includes variables available on the Microdata API, including microdata access on data.census.gov (MDAT).
A basic explanation of the sample design, estimation methodology, and accuracy of the data.
List of variables with responses exceeding a state-specific value that are replaced with a predetermined value.
Note that some of these estimates may be different from the estimates for the same characteristics published in data.census.gov. For an explanation of these differences, see the Accuracy of the PUMS above.
Counts of unweighted records for each PUMS file.