Silver Book Fact
Increased longevity added about $3.2 trillion per year to national wealth between 1970 and 2000, an uncounted value equal to approximately 1/2 of the average annual GDP during that period.
Murphy K, Topel R. The Value of Health and Longevity. National Bureau of Economic Research Working Paper. May-2005; 11405. http://www.nber.org/papers/W11405