Well, little or nuthin', actually. This got a wry grin outta me:
It really pains me to throw food away but it DOES happen from time to time. Cooking for One will do that to ya, especially when most food packaging is designed for families rather than single people. That said, I don't come CLOSE to throwing 40% of my food away. The high end estimate would be quite a bit less than ten percent, if I had to guess.