Passenger yield (Passenger Revenue per Revenue Passenger Mile) for American has decreased slightly in recent years due to competition from low-cost airlines and poor domestic economic conditions.

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Domestic Passenger yield (passenger revenue per revenue passenger mile) for UAL has decreased slightly in recent years due to competition from low-cost airlines and poor domestic economic conditions.

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In the meantime, the number that really matters--called the "yield, " or the price a passenger pays to fly one mile--fell 4.5%.

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