Wrt not counting non-Scottish pax, the remainders seem bit high. If they are correct they show that all three airports have very few foreign originating pax, which I do not believe.
Maybe I did not make myself clear. It assumes that those arriving at EDI (or any of the other airports listed) whose final destination is not central belt or departing where their journey start point is not central belt will be excluded. Non UK pax will be included where appropriate as it is based on ultimate destination for arriving and start point for departing regardless of nationality.
So a passenger arriving from Germany will be counted in the EDI stats if they plan to stay within the EDI catchment area and will be included again when they depart for the same reason if they are still in the same area.
Does that make more sense?
Ex