It is interesting that 5th series was a winter release, I had tons of 5th series stickers. 10th and 11th were the next winter, I didn't get many of those stickers. Maybe by then some of the stores had stopped carrying them, as the craze was waning. I had the kind of parents who would let me buy them at grocery or drug store if they were already there or even going by, but they were not about to make a special trip so I could "waste" some nickels....