How many dead profiles are on there? I've just deleted mine, and in my circle of "friends" there were about 20 out of 350 that had updated their profile within

How many dead profiles are on there? I've just deleted mine, and in my circle of "friends" there were about 20 out of 350 that had updated their profile within the last year. Is there some kind of pareto distribution where Facebook has found its 'whales' that it can attract, and silently dropped all the other users, but kept their dead profiles?