Issue regarding program copies...

I'm in the process of completely wiping my system clean. Being a graphic designer, I do this with all of my computers every year or so, upgrade to new OS's and upgrade hardware among other things. I've realized that I only have one activation remaining for a new PC and I'm wondering...

 

If I wipe my computer clean (by wipe, I mean total 'clearing, upgrading to Win7, everything that was there before - gone kind of clearing) , will that count as a 'new computer"? I want to have virus protection on the 'new' computer, obviously, and I've recently re-upped for two years so I'm curious as to what I should do. I would like to keep one activation on backup in the event I buy another computer or have some sort of catastrophic problem in the future.