Passenger-Miles

The total number of miles traveled by transit passengers (e.g., a bus that carries 5 passengers for a distance of 3 miles incurs 15 passenger miles). (FTA2)

The cumulative sum of the distances ridden by each passenger. (FTA1)

The total number of miles traveled by passengers on transit vehicles; determined by multiplying the number of unlinked passenger trips times the average length of their trips. (APTA1)

One passenger transported 1 mile. Passenger miles are computed by the summation of the products of the aircraft-miles flown on each inter-airport flight multiplied by the number of passengers carried on the flight. (DOE6)