Ideally, we want to do continuous descent with every aircraft. Ideally, we have an aircraft from top of descent—that's cruise altitude—coming on continuous descent all the way to the runway. We'd like to use that as much as possible.
We do have to use levelling sometimes to provide separation between aircraft. One of the ways we separate aircraft is vertically. You can have 1,000 feet of vertical separation and that does require us to level off an aircraft at times. As we move forward, a lot of the work we're doing internationally and as a company is to promote increased continuous descent operations. That's certainly a priority for this organization.