Capacity-controlled fares

Capacity-Controlled Fares: A limited number of airplane seats to which a special fare has been assigned. This percentage may change depending upon how quickly seats are selling on the flight.

Capacity-controlled fares - a certain number of seats on a flight to which a cheaper price has been allocated. This percentage changes depending on how quickly the seats are sold.
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See also: Check-in, Carrier, City pair, Ticket, Standby