Wow, it can be way more common to lose your bag than I would have thought -- on Aer Lingus, a 1 out of 57 chance! (While Delta is 1 in 497, and Air France is 1 in 1,256 -- more what I expected.)

But the national aspect is seemingly even more interesting -- in India you have a 1 in 97 chance, while in the US it's 1 in 497, and in Japan it's 1 in 7,734.

Now I'm incredibly curious to know what the real, actual culprits are. To what extent is is about the check-in airport or connecting airport that loses it, to what extent is it about airline policies around how luggage is handled, and to what extent is it national regulation that sets standards for airline performance, airport performance, or both?

Because the amount of variation here is just astounding and far, far, beyond anything I would have guessed. I would have naively figured that lost luggage was at a relatively "economically efficient" level and would therefore be pretty similar across airlines and countries... when clearly that is not the case at all.