FWIW: Cup size is an increase in circumference, not length. And cup size is a relative measure. A "D" cup is supposed to mean that the fullest part of the breast is 4 inches more than the ribcage in circumference. So a 34D is going to be much less mass than a 44D (but, ironically, also a lot "fuller" looking relative to the rest of her figure). The last statistics I heard: The average American woman is about 5'4" tall and a size 16 dress size. More girth around the ribcage due to weight means "average" cup sizes that equal more mass because cup size is very much relative to that initial ribcage measurement. (I'm reminded that not long ago there was an article posted on HN apparently about women getting both shorter and fatter on average -- or so I gathered from the comments.)