Hint: It has something to do with your legroom.

American Airlines wants to fit more passengers on its new planes, and that would mean less legroom for those in economy.

Up to two inches less, CNN Money reported.

American's economy seats currently have a seat pitch (the distance from a point on one seat to the same point on the seat in front or behind of it) of 31 inches, but the new Boeing 737 MAX airplanes could have economy seats as close as 29 inches. The change would make it possible to fit 170 seats on the plane, instead of the previous 160.

CNN Money reports this would make American the first major U.S. carrier to have a seat pitch that rivals low-cost carriers like Spirit and Frontier. Delta, Southwest and United offer a seat pitch of 31-33 inches in economy, depending on the aircraft and the particular row.

It's possible that the decrease would not directly correlate with a loss of legroom: The backs of the new seats are designed to be slimmer. Of course, the comfort level of a slimline seat can vary.

No matter how comfortable the seats end up being, further reducing the space/comfort/services afforded to economy passengers is an industry-wide trend. Earlier this year, American introduced a “basic economy” airfare that offers basic service for travelers who do not need things like assigned seats or overhead bin space.

If you value comfort, it might be time to educate yourself on airlines' “premium economy” offerings.