MIAMI — Delta Skymiles members will begin to earn miles based on fares paid starting in 2015. The program was previously based on how far a participant flew, and marks the first major legacy carrier to make such a change.

“The current distance-based model was developed 30 years ago when fares were highly correlated to distance,” says Jeff Robertson, Delta’s vice president of SkyMiles. “We think the spend-based model allows us to invest more in our premium customers and is right for Delta today.”

Up until now, SkyMiles members who spent $500 on a flight earned the same amount of miles as one who spent $5,000. Delta’s decision to peg the reward program to a pay-more-to-play-more style is likely to anger lower tier, lower paying customers. But it will likely make the biggest spenders in the 91-million strong program quite happy.

Depending on their status, members of the program will earn between five and eleven miles per dollar spent flying on Delta. Have the SkyMiles credit card? Add another two miles per dollar, boosting the max possible earnings to 13 miles per dollar for a diamond member:

SkyMiles program status Miles per dollar* Miles earned with Total miles per
General member 5 +2 7
Silver Medallion 7 +2 9
Gold Medallion 8 +2 10
Platinum Medallion 9 +2 11
Diamond Medallion 11 +2 13

*[on Delta spent] – Source info for chart from Delta Air Lines

Perhaps most importantly, however, the airline has not released fully updated redemption charts. The charts, which are used to determine how many miles are needed to earn a free upgrade to first class, or a round-trip vacation in coach to Europe, will be released at a later time. Changes, up or down, alter the value of the miles.

Still, Delta did announce a new mileage redemption structure which it says will improve award seat availability at the lowest mileage requirement levels. Also, the company will offer one-way awards at half the price of round-trip, provide additional miles + cash award options, as well as make improvements to and Delta reservations award shopping tools. Where those trips can be found in the system, is again still unclear.

Wednesday’s announcement is not the first revenue-based move the carrier has made with its loyalty program. Delta announced in January of 2013 that members would need to spend a minimum of $2,500  to qualify for the lowest status ring. Previously that feat could be achieved solely by miles flown.

Still,  the revenue-based loyalty program strategy is not new. Virgin America became the first airline to tie ticket price to earning of loyalty points in 2007. JetBlue and Southwest also utilize a revenue-based model. While not a guarantee, it is likely other legacy carriers will wind up following suit.