average lifespan of the elite roman class?

[SwissBarbar]

The lower average lifespan of ancient times, is because of the higher infant mortality. If one had survived his first - say 10 - years, there was quite a good chance for him to get 60-80 years....

Remember Augustus. He's said to have had quite a weakish, morbid health, but still got very old (76 years, IIRC)