I think that while many of them are headed for the desert, there will still be a sizable fleet of them left until the end of the decade. Maybe 70 or so. If they are paid for, or have really low lease payments, why get rid of them so fast? Whenever the next economic recession hits, it would be to the airline's advantage to have a number of aircraft that they can mothball at a moments notice, to cut capacity, which do not have a hefty payment due each month. The 319s and 320s from the US-east side were delivered starting in 1999. So they still have some life left in them. There are some older 320s on the US-west side. But I think those are starting to be retired next year.