Report an error

Correcting quickly and in public strengthens a source. Hiding an error destroys it.

How to report

Write to corrections@bertrande.com with the page address, the figure you believe is wrong, and the source you are relying on. A link to an official page is the fastest route.

What happens next

We check the figure against the source we hold, and against the source you send. If we were wrong, we add a new observation with the corrected value. We never edit or delete the old one, because rewriting history would defeat the purpose of this site. The correction therefore appears as a dated change, visible to everyone.

If a value looks stale rather than wrong

Pages mark a value as due for re-checking when it has not been verified within three times its expected cadence. If you see that marker, the figure may simply be waiting for its next check.