skeptical

Jim Cramer's Mad Money In-Depth, 1/2/08: A Look Back, A Look Ahead

I don't understand how Cramer came up with a 16% + return on his picks in 2007. Apple was up 150%+ & he had another good winner but lost 50% in LVLT & Rite Aid. Did he put equal $$ into each of his picks ?
What methodology did he use ?