About 10 to 30 percent of stars quit the business after making one film. Tom Byron has 2,549 film credits since 1982. Nina Hartley, who started in 1984, has made 938 porn films. The top 10 women have slept with 148 men, or eight a year for an average of 17.7 years. From that come gems such as this: The top 10 most-prolific male porn stars have slept with 1,013 women each, or 45 a year for an average career length of 22.4 years. The largest woman weighed 719 pounds, and the lightest was 74 pounds. The average male is 167.5 pounds, or 27 pounds less than the national average for men. The average male porn star is 5 feet 10 inches, while the average woman is 5 feet 5 inches - the same as the average American man and woman.The average female is 117 pounds, or 48 pounds under the U.S. And dark-haired porn stars outnumbered blondes by two to one. The most common set of measurements for women was 34-24-34. Double-D bra sizes were fourth, behind B, C, and D. Based on his review of about 8.6 percent of the database’s profiles, the average porn star has a bra cup size of 34B. Millward wrote that the impression of a porn star as a “blonde with big boobs” is actually wrong.