Above is our itinerary for one of our upcoming travel which was sent over to us by our TA in which they generated through their GDS system after we had paid and had our tickets issued. As you can see, there is a section on the itinerary for each flight that indicates "Distance (in Miles)" which for us are listed on that piece of itinerary as 7,810 miles for each direction. This 7,810 miles is the exact same number to be found on the Great Circle Map when inputing the city pairing. So if we go according to such, then the number of mileages we are to earn would be 23,430 [7,810 X 2(Roundtrip) + 50%]. However, MPO/Asia Miles' calculated distance in miles is listed as 7,796 miles for this route each way which is 14 miles less than the ones according to the GDS/Great Circle Map. So for this trip we would be earning 23,388 MPO/Asia Miles [7,796 X 2(Roundtrip) + 50%] (as always the case whenever we fly paid "First" on this route) which is 42 miles shorter than what would be the amount if we were to follow the mileages provided by the GDS/Great Circle Map. By bringing up this subject, we are by no means trying to be greedy for extra mileages nor are we expressing any disappointment that we are going to earn 42 miles less into our accounts. But rather we are just curious how CX calculates (or the system they use to calculate) the distance mileages before applying any bonuses for the applicable traveling class as it is apparent that MPO/Asia Miles' distance calculation are not the same with that found on the GDS/Great Circle Map though clearly evident the differences are not big at all. We are just curious on how the calculation is done on CX's behalf, that's all.