• Airlines use Revenue Per Available Seat Mile (RASM) to measure the total operating revenue they earn per seat (empty or full) per flight mile.

  • Airlines prefer to use RASM as a measure of their financial performance as it includes additional sources of revenue such as baggage fees, rebooking fees and in-flight meals.
  • The revenue per seat mile (RASM) calculation is total operating revenue divided by the number of miles per available seat.