Sources & methodology

1. We fetch what the authority publishedthe original file or feed, kept as it arrived
2. We map it to airports and periodsby ICAO and IATA code, never by name alone — three-letter codes collide
3. We label what it coversall traffic, domestic only, international only, or tracked by receivers rather than counted
4. We pick one source per figurewhen two authorities report the same airport-month, the more complete one wins, and the page names it
5. We never mix labelsa domestic-only series is never added to or ranked against a full-coverage one

Each source keeps its own rhythm: 3 publish daily, 36 monthly, 10 quarterly or yearly. We re-check each one on its own rhythm and republish as soon as new figures arrive.

12 sources feed the environment sections on airport, airline and country pages — European Union and United States only. Each is listed with what it covers, how far back it goes and the credit its licence requires.