PUMS Technical Documentation

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PUMS Technical Documentation

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 PUMS Data page.

2018

PUMS ReadMe

Important information about 2018 geography and variable changes, as well as guidance for novice ACS PUMS files users.

2014-2018 ACS 5-year PUMS ReadMe [<1.0 MB]

2018 ACS 1-year PUMS ReadMe [<1.0 MB]

Subjects in the PUMS

A list of topics included in each of the housing and population record files

2014-2018 ACS 5-year PUMS Subjects [<1.0 MB]

2018 ACS 1-year PUMS Subjects [<1.0 MB]

PUMS Data Dictionary

Includes variables available for each PUMS release and how each variable is coded

2014-2018 ACS 5-year PUMS Data Dictionary [<1.0 MB]

2018 ACS 1-year PUMS Data Dictionary [<1.0 MB]

Code Lists

Detailed codes for variables that contain a large number of coded responses, such as ancestry and occupation

2014-2018 ACS 5-year PUMS Code Lists [<1.0 MB]

2018 ACS 1-year PUMS Code Lists [<1.0 MB]

PUMS Top Coded and Bottom Coded Values

List of variables with responses exceeding a state-specific value that are replaced with a predetermined value.

2018 ACS PUMS Top & Bottom Coded Variables [PDF] [<1.0 MB]

2018 ACS PUMS Top & Bottom Coded Values [CSV] [<1.0 MB]

Accuracy of the PUMS

A basic explanation of the sample design, estimation methodology, and accuracy of the data.

2014-2018 ACS 5-year PUMS Accuracy [PDF] [<1.0 MB]

2014-2018 ACS 5-year PUMS Design Factors [CSV] [<1.0 MB]

2018 ACS 1-year PUMS Accuracy [PDF] [<1.0 MB]

2018 ACS 1-year PUMS Design Factors [CSV] [<1.0 MB]

PUMS Estimates for User Verification

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.