Googling on "bra size average" presents this from sexualrecords.com: Average Bust Size The average bust line for American women is 35.9 inches (91.2 cm). The typical bra size is 34B, with the proportions of women's cup sizes breaks down to the following: A-15%, B-44%, C-28%, D-10%, while the remaining 3% are AA, AAA, DD and beyond. Interestingly, manufacturers of women's clothing agree that the average American woman's bust size has expanded in recent decades, if only by fractions of an inch, due to improved diet and birth control pills. So the typical Poser female will undoubtedly be within that 3% containing the DD+ sizing. =)