My usual observation:

There are a lot of air forces around the world. Individual not as big and not as much flying as the USA'S three air forces, but together with an awful lot of flight hours and for some air forces the same jets flying with the same or similar sensor packages. And then there is commercial aviation which dwarfs everything else in flight hours.

But for some reason UFO/UAP sightings seem to happen mostly in the US and the US southwest.