How often are these data revised?

The Census Bureau revises historical data each June for the three immediately preceding calendar years. For example, in June 2024, Census published revisions impacting trade statistics impacting data for 2021, 2022, and 2023 calendar years. The USITC’s DataWeb incorporates these Census Bureau revisions shortly after their publication, but because they are revising thirty-six months of data it typically takes the USITC slightly more time to update the database than with the normal monthly releases. 

The data subject to these annual Census Bureau revisions are separately posted by the Census Bureau in a running spreadsheet format on its corrections page. Users wishing to know whether any specific country or HTS number may be impacted by a future Census Bureau revision release may check this website: https://www.census.gov/foreign-trade/statistics/corrections/index.html. If an error is discovered more than three years in the past, the correction will not be reflected in the official US trade data or in DataWeb.