weight class smoker lifespan 3 0 50.3 3 0 52.8 3 1 54.7 3 0 56.0 2 0 58.1 2 1 60.2 2 0 62.8 2 0 64.5 1 1 66.3 1 0 68.4 1 0 70.2 1 1 72.1