At what age did you find out that Santa wasn't real?

My parents never told me Santa was never real. They always filled my stockings on Christmas morning. I just started to get suspicious when I saw things in my stockings around the house a few days earlier. Then one Christmas morning my parents didn't put anything in my stocking because I had been misbehaving and lets just say to put it lightly i was pretty upset. I must have been 11 or 12 i think that might be a little old for crying but i get emotional and it was hard to believe in a guy who could do all of that in one night seemed impossible. Its kinda funny now when I think of Santa becuz would you really want some fat old man to come into ur house into the middle of the night and rummage through your livingroom stop by your kids room your daughter! It just seems like the whole security of having Santa come into your house would be broken.