 We're going to do our best to characterize the environment, we're going to do our best to put a plan together, then we're going to step forward and the first thing you've got to do is measure to see, are you having the effect that you designed, you know, that you intended. There's a lot of uncertainty and I think this kind of, you know, measuring as you go and adapting as you go is fundamental to our use of the word design rather than plan.