[PMan74]

OAG aggregate timetable data from airlines and distribute that aggregated feed.

You'll note their data is "seats" not "passengers" i.e. if an A380 flies from London to Dubai they count that as 525 seats as opposed to however many people took the flight.

[FabHK]

Good point. Might, then, also reflect pressure from governments to keep flying, no matter the pax load factor.