How are bras sized? Is there a variety of measurement units for chest circumference? Is it the same size as a bra?

Give you a picture to understand. But that's the representative of China. In Europe and America, they use 32=70, 34=75, 36=80, 38=85 and so on.

The skeleton of Europeans and Americans is bigger than that of our orientals, so they don't have a lower circumference of 65 cm, which is 30 yards.