The COVID-19 pandemic resulted in substantial mid-year changes in the landscape of certain social safety net programs in the U.S.; however, 2021 SIPP data do not fully reflect known volatility in the Supplemental Nutrition Assistance Program (SNAP, also sometimes called food stamps) and unemployment insurance (UI, also sometimes called unemployment compensation). In response to these data concerns, the Census Bureau released the below supplemental research file that contains experimental versions of SNAP and UI estimates, derived using experimental edit and imputation processes. Please see the working paper Is there a Safety Net for Surveys? for more details about this file.

This research file does not replace the base 2021 SIPP data. It is instead released as a supplement to 2021 SIPP data to promote conversation about these estimates and the processes by which they were derived to improve future estimation of these and other social welfare and social insurance programs.

For questions about SIPP data, visit the Contact Us page.

2021 SIPP Research File Technical Documentation

2021 SIPP Research File Release Notes [< 1.0 MB]

2021 SIPP Research FIle Data Dictionary [< 1.0 MB]

2021 SIPP Research File Crosswalk [< 1.0 MB]

2021 SIPP Crosswalks - 2021 to 2020 [< 1.0 MB]

Working Paper

Is there a Safety Net for Surveys?

This SIPP working paper describes the creation of alternate SNAP and UI measures using experimental processes to account for program volatility during COVID.

Data and Documents links - Research Data File

The 2021 SIPP Research File data, in SAS, STATA, and pipe-delimited text formats, compressed as zip archives.

Supporting Documents

Data Disclosure Statement

The U.S. Census Bureau reviewed these data for unauthorized disclosure of confidential information and approved the disclosure avoidance practices applied to this release. CBDRB-FY23-0353.