If the 360 sells 30 million total within 2 years, CoD4 only needs a 13% attachment ratio in order to sell 3.9 million copies. You had said 4+ million and the stock is not at 4 million, it's at 3.71 million. So the attachment ratio right now would only have to be 12.5%. That means only 1 in 8 360 owners would need to buy the game within the next 2 years. If we take CoD 2's sales and even put them up against 10,000,000 360's sold, CoD 2's attachment ratio is over 20%. To think CoD2 can have an attachment ratio of 20% but CoD4 can't even reach 12.5% is a little off IMO.
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