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User Notes

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User Notes

Within Technical Documentation

Code Lists, Definitions, and Accuracy
Data Release Rules
Errata Notes
Table & Geography Changes
Table Shells and Table List
User Notes

User Notes

Learn more about issues impacting the American Community Survey, including design, collection, production, and data release. The notes are sorted by data collection year(s). If the user note pertains to multiple years, the note will appear in the tab for each year.

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User Notes

Population Controls and Other Methodology for the 2024 ACS 1-Year Estimates

September 2025
User Notes

Changes in the Occupation Estimates of Office and Administrative Support Workers, All Other

September 2025
User Notes

Suppression of 2024 ACS 1-Year ACS Comparison Profiles for AL, GA, LA, NY, and NC Congressional Districts

September 2025
User Notes

Overlapping Race and Ancestry Estimates in the ACS Data Products

September 2025