Year Percent 1950 15.83406 1955 14.99551 1960 14.12654 1965 13.46495 1970 13.0638 1975 12.81817 1980 12.95517 1985 13.38437 1990 13.7602 1995 14.96663 2000 16.26336 2005 17.5864 2010 19.07193 2015 20.08688 2020 20.97709 2025 21.86947 2030 22.78166 2035 23.55559 2040 24.19089 2045 24.46789 2050 24.61089 2055 24.73407 2060 24.80716 2065 24.91712 2070 24.81694 2075 24.5769 2080 24.28904 2085 23.99636 2090 23.706 2095 23.40579 2100 23.10438