In-Reply-To: <199412041944.OAA13406_at_hops.wharton.upenn.edu>
> From: Nick Brooke <100270.337_at_compuserve.com
>_________
> Nick Eden:
>
> > If almost no-one survives to the age of 45, then there's very little
> > point of making a big thing about the retirement benefits. And yet
> > they did. Therefore the 40 figure, though widely quoted, isn't up to
> > much.
>
> Nah, you've missed the point. If life expectancy *at birth* is 40 years,
> andhalf of all infants born die in their first year of life, then the
> averagelength of life for the survivors is 80 years! See? Check out the
> UN figures Iposted a while ago if you want some hard data. Average life
> expectancy is auseful measure, but you have to be careful with it... in
> this case, for alltheir sins, the Roman Army did not recruit newborn
> babies; so the sprogs' lifeexpectancy is irrelevant. Once you'd survived
> to enlisting age, you're alreadypast the big glut of deaths (excepting
> those caused by being in the Army,naturally!).
I think that was my point as well. The 40 figure is widely quoted - I
remember a Dragon article on that basis a couple of years ago, and while
it has meaning, it doesn't mean what Dragon article writers often seem to
think it means.