Airline loyalty programs for the big three U.S. carriers Delta, United and American Airlines are now about dollars spent versus miles flown.

Delta first moved from a system that awards miles based on flight distance to one that recognizes how much a customer spends with the airline. United followed, matching a revenue-based scheme that had been used previously by airlines such as JetBlue and Southwest.

Last month American became the latest carrier to change-up its program, now awarding passengers miles based on the price of the ticket purchased. And award redemption levels will be calculated on a flown basis, so whatever a passenger’s status is when they fly those actual segments, that will be the multiplier used for that segment.

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