That's one of the powerful incentives of this program. There are a couple things that the F-35 does differently from previous fighter fleets. One is that the airplane never becomes obsolete. Nine nations in the partnership have invested in long-term software upgrades. It's a jointly led program funded through the partnership, and is part of the in-service support costs. Every two years, the aircraft softwares will be upgraded and retrofitted to all the fleets. You're never more than two years out from the latest software upgrades for the airplane, and this is something that we've never had with any of our fleets.
With the F-18, we had to spend a significant amount of money on software upgrades and hardware improvements to bring the airplane, after 20 years, back up to international standards. The F-35, throughout the life of the aircraft, will always be within two years of the latest aircraft coming off the factory floor, which is something we've never had before. That's leading-edge technology for the life of the program.