Charts from OKCupid, showing how straight women and men rate each other based on ages. For women, the men they find most attractive are roughly their own age. For men, the women they find most attractive are roughly the same age - 20 to 23 - regardless of the age of the man. (538)
You know how to make the same chart even creepier? Start at 16 instead of 20 and look how the bottom chart will look then.