Preserving the information available at a decision time
The vintage path separates the period measured from the publication date of each available value and retains revision history.
A reference date identifies the period measured. A publication date identifies when a particular value became available. Filtering a revised series by reference date alone can introduce information that was unavailable at the decision time.
Alelyon’s vintage adapter distinguishes first release from the available revision sequence. A missing key or an initial fetch failure can produce an empty result with a diagnostic reason. An interrupted paginated fetch can return and cache partial rows, so a nonempty result does not establish complete coverage. Consumers must retain that limitation and must not substitute a current value under a historical label. The FRED real-time documentation explains the provider’s real-time interval semantics.
Consumer record
Retain source, series, reference period, requested as-of time, returned publication date, retrieval time, and data-quality status. Establish timezone and release time separately when an intraday decision depends on them. Revision discipline covers one information boundary; it does not model liquidity, fills, or transaction costs. See the integration guide.