I think Lynx Arc nailed that about right on the head, for general population. What you didn't take into account is that most countries issue flashlights to military officers, navy, air force, LEOs, moive casts, TV shows, Home inspectors, ect ect. I would guess that each person in each one of these departments has at least 5 more lights then the normal person, or course I dont think most CFPers are "normal" in the flashlight department but thats beside the point. Figure 500 million that get 2 lights every 2 year so that would up 1/4 a billion a year to 1/2 a billion a year. I know for sure lots of government agencies replace their lights very often.