Pursuant to a congressional request, GAO reviewed the Census Bureau's plans for coverage evaluation and adjustment of 1990 census figures. GAO found that the Bureau is considering an adjustment of the 1990 census counts to correct errors in data used to redistrict state legislatures and distribute federal funds, and plans to: (1) conduct the most complete census possible; (2) adjust the counts by the legally mandated deadline, if an adjustment would improve the counts; and (3) use a large-scale post-enumeration survey (PES) of 300,000 households and demographic analysis as the methodologies for measurement. Because the Bureau's error estimates in the 1980 census contained inaccuracies, it developed an automated matching system designed to accelerate matching PES and census records.