Cost index surely should change dependent on network, fuel price fluctuations, operational costings and hedging agreements. Personally I believe that our standard cost index is due to our operational department being so understaffed and it's planning equipment being so inept. Besides, ECON speeds are rarely adhered to anyway, so fuel burn figures based on a perceived standard cost index will be largely inaccurate anyway. Maybe I'll punch in CI 500 next time I fly
