The only measure of productivity between pilot groups is block hours flown per pilot. Aircraft usage goes up and down with the economy, marketing and type of operation. Usage varies quite a bit at Delta even among narrow body fleets. At the moment as a example we have a surplus of MD88/90 airframes and could fly them more if marketing decides the economy is improving by adding pilots. We needed as many as 35 pilots for each 777 but that is because of high daily hours flown and the need for 3 and 4 man crews.