The math is roughly like this: Assume for simplicity that starting from age A, after n years have passed since then (n >= 1 an integer), a fraction d_non(n) of nonsmokers dies during the year A+(n-1) <= t <= A+n. Then after M years there is a fraction S_non(n) = Prod_{1 <= k <= M} (1-d_non(n)) of nonsmokers who have survived from age A to age A + M. For smokers, assuming for simplicity that during the nth year after age A: d_smoke(n) = 2.7 d_non(n), then after M years there is a fraction S_smoke(n) = Prod_{1 <= k <= M} (1-2.7 d_non(n)) of smokers who have survived from age A to age A + M (assuming the death ratio of 2.7 holds each year starting from age A). --Dan

On Feb 14, 2015, at 12:58 PM, rcs@xmission.com wrote:

If the death rate from smoking is 2.7x nonsmoking, does it follow that, since American life expectancy is 80 years, that smokers only live to be 30?