Every collector writes a completeness record on each run — how many intervals arrived versus how many were expected for that delivery day. This page reads those records directly. When a feed breaks upstream, it shows here rather than quietly turning into a gap in your backtest.
Completeness is measured against expected interval counts per source and delivery day, so a value below 100% usually means the upstream publisher hasn't released the full day yet — not that data was lost. Sources publish on their own schedules, and some (JAO, fuel prices) are daily rather than intraday. Historical revisions are retained: corrected values from upstream are stored as new revisions rather than overwriting what was originally published.