FRED has established a formal procedure to ensure the accurate publication of data from trusted sources:

• Data downloads are checked for accidental corruption of the electronic files.
• Each new download of a data series is checked against its existing counterpart in FRED. Unexpected values or other elements are flagged for review, and the data source is contacted for clarification.
• The reported data frequency and the formats of data values and dates are verified.
• The sign and magnitude of data values are checked for accuracy. Any significant discrepancies with previously reported data, including missing or dropped values, are flagged, and the data source is contacted for clarification.

Only then are new data values added.

After the FRED Team validates each new version (or vintage) of a data series released by a source, FRED displays the latest version. The replaced version is archived in ALFRED.