Largest Bra
In September 1990, in Tokyo Japan, Triumph International Japan Ltd developed a bra with an underbust measurement of 78ft. 8in., and a bust measurement of 91ft. 10in. (Source: Guinness Book of World Records)

Statistics
Studies show that 50-75% of women today are not wearing the correct size bra.
Over the last 15 years, the average bra size has increased from 34B to 36C.
The average fashion is designed for a B-cup size breast.

Miscellaneous
Cup sizes rage from AA-JJ.
Women have used bra-like devices, designed to lift, separate and restrain their breasts since as early as 2000BC.
A bust size of 34B bounces 3^1/8 inches (8 centimeters) with each step when running. (This is why it is important to wear a supportive bra when exercising)