How much weight to lose to get a flat stomach?(pics)?

I have an overhanging stomach, but I’ve never been preggo or anything.
I’m currently 171lbs in this video; which was my weight on Sunday, Oct 13. How many lbs do you think I have to lose to lose the overhang? Not completely flat and perfect, but just enough to get rid of that.

http://www.youtube.com/watch?v=jcYurnALemI&feature=player_profilepage