This page provides guidance for people interested in working with CPS ASEC public use microdata. Public use microdata files are available for use with statistical software such as SAS, STATA, and SPSS. In accordance with Title 13, U.S. Code, CPS ASEC public use microdata files do not contain personally identifiable information. This is to protect respondent confidentiality. In some cases, data have been altered, or “perturbed,” to further protect confidentiality. As a result, population estimates derived from CPS ASEC public microdata may not exactly match those reported in pre-tabulated CPS ASEC data tables.

Details about downloading and using CPS ASEC public use microdata are available at https://www.census.gov/data/datasets/time-series/demo/cps/cps-asec.html. This page, titled “CPS March Supplement,” contains six documents for each data year:

1.      Technical documentation

2.      Data dictionary

3.      Data file

4.      Replicate weight usage instruction

5.      Replicate weight SAS input statements

6.      Replicate weight data file

CPS ASEC data can be downloaded from the website as a general DAT file. It can then be converted into a SAS or other dataset. The data dictionary will help with the SAS file layout.

The replicate weight usage instructions, replicate weight SAS input statements, and replicate weight data file all concern the calculation of standard errors. In short, the replicate weight usage instructions explain how to create a master file by merging the person, household, and replicate weight files. Replicate weight SAS input statements include suggested SAS code to create a replicate weight SAS dataset.

Users wishing to obtain CPS ASEC public use microdata in customized tabular format may also request a special tabulation at https://www.census.gov/programs-surveys/popest/data/special-tab/request.html).