Well it is a percentage of the mainline fleet. And they are basically at the max now. The next few years will see a lot of new aircraft at mainline and some new RJ's that will probably see the 40% match. From then on, if a mainline aircraft leaves and not replaced, an RJ must also leave. And if they want more RJ's, they can have them as long as more mainline aircraft are added to keep the percentages in line.

I would be curious to know the percentage limit at Delta and United...