@inbook {14381, title = {Is The U.S. Population Behaving Healthier?}, booktitle = {Social Security Policy in a Changing Environment}, year = {2009}, url = {http://www.nber.org/papers/w13013}, author = {David M Cutler and Edward L. Glaeser and Allison B. Rosen}, editor = {Jeffrey Liebman and David M Cutler} }