The Census Bureau Should Address Challenges from the 2020 Post-Enumeration Survey Ahead of the 2030 Census - Final Report - Report No. OIG-25-015-A

Oct 3, 2026

Upload by Elsa

Final report OIG-25-015-A on the U.S. Census Bureau’s 2020 Post-Enumeration Survey (PES) evaluates whether PES methodologies were consistent with relevant federal and agency statistical standards and whether PES operations produced accurate, reliable overcount and undercount estimates. The audit finds operational disruptions and mitigations increased uncertainty due to missing data, a smaller-than-anticipated sample size reduced precision, and planned quality control processes were not completed as designed. The report provides actions to address these issues in the 2030 PES redesign.

LanguageEnglish

CategoryResearch & Report

FormatPDF

Pages43

Reading Time1 h 48 min

AccessFree to download

Background

What the 2020 PES is for

Why the review was needed

What we found

Missing data and non-sampling error quantification

Smaller-than-anticipated sample size

Quality control (QC) process shortcomings

What we recommended

The Census Bureau Should Address Challenges from the 2020 Post-Enumeration Survey Ahead of the 2030 Census FINAL REPORT NO. OIG-25-015-A MARCH 25, 2025 The Census Bureau's Disclosure Review Board and Disclosure Avoidance Officers have reviewed this information product for unauthorized disclosure of confidential information and have approved the disclosure avoidance practices applied to this release. (CBDRB-FY24-0479) U.S. Department of Commerce Office of Inspector General Office of Audit and Evaluation March 25, 2025 MEMORANDUM FOR: Dr. Ron S. Jarmin Acting Director U.S. Census Bureau FROM: Analee Striner-Brown Acting Assistant Inspector General for Audit and Evaluation SUBJECT: The Census Bureau Should Address Challenges from the 2020 Post-Enumeration Survey Ahead of the 2030 Census Report No. OIG-25-015-A Attached is the final report on our audit of the U.S. Census Bureau’s 2020 Post-Enumeration Survey results as they relate to overcounts and undercounts. We will post the report on our website per the Inspector General Act of 1978, as amended (5 U.S.C. §§ 404, 420) . Within 60 calendar days, please provide an action plan addressing the report’s recommendations, as required by Department Administrative Order 213-5. Please also note that any nongovernmental organization or business entity specifically identified in this report can submit a written response to clarify or provide additional context on any specific reference (Pub. L. No. 117-263, § 5274). The response must be submitted to Amy Jones, Division Director, at [ajones@oig.doc.gov](ajones@oig.doc.gov) and OAE_[Projecttracking@oig.doc.gov](Projecttracking@oig.doc.gov) within 30 days of the report’s publication date. We will post the response on our website as well. If the response contains any classified or otherwise nonpublic information, the organization should identify the information and provide a legal basis for redacting it. We appreciate your staff’s cooperation and professionalism during this audit. If you have any questions or concerns about the report, please contact me at (202) 893-8759 or Amy Jones at (724) 343-6921. Attachment cc: Deborah M. Stempowski, Associate Director for Decennial Census Programs, Census Bureau Maureen Mellody, Ph.D., Associate Chief Program Officer, National Research Council Executive Office, National Academies of Sciences, Engineering, and Medicine MARCH 25, 2025 Background The U. S. Census Bureau carries out a decennial census of the U.S. population to reapportion the U.S. House of Representatives and determine the distribution of federal funding to the states, tribal governments, and local communities for services and infrastructure. The bureau also carries out a quality check of the decennial census, which in 2020 was called the Post-Enumeration Survey (PES) . The PES’s purpose is to independently survey a representative sample of households from the decennial census enumeration to measure coverage error and census accuracy. The PES results are one of the most important quality measures of the decennial census. This is especially true for the 2020 Census, which experienced complications and delays largely due to the COVID-19 pandemic—particularly with the Person Interview (PI) operation. Because of a low response rate at the end of the original operation compared to 2010, the bureau decided to reopen PI to increase response rates. PES estimates found that 14 states had population undercounts or overcounts. In addition, some historically undercounted demographic groups were undercounted again, but to a higher degree, while others were overcounted. Why We Did This Review Our audit objective was to assess the validity of the 2020 PES results as they related to overcounts and undercounts. We assessed (1) whether the bureau’s methodologies for carrying out the 2020 PES were consistent with relevant federal and agency statistical standards and (2) the effectiveness of 2020 PES operati

FAQs

What was the audit objective for the 2020 Post-Enumeration Survey (PES)?

The audit assessed the validity of the 2020 PES results regarding overcounts and undercounts, including whether PES methodologies followed relevant federal and agency statistical standards and whether PES operations were effective in producing accurate and reliable estimates.

What major factors did the audit identify that affected the PES results?

The audit identified increased missing data and insufficient quantification of non-sampling error, uncertainty increased by operational disruptions, a smaller-than-anticipated sample size, and quality control processes not executed as planned, including issues with independent listing QC, person interview reinterview timing, and basic collection unit reviews.

What actions were recommended for the 2030 PES redesign?

The report recommended advancing approaches to mitigate missing data and conducting research to better understand groups most likely to be impacted by missing data as part of implementing changes to the 2030 PES redesign.

Oct 3, 2026

Upload by Elsa