Year Percent 1950 27.01634 1955 27.44951 1960 27.71581 1965 27.92546 1970 27.95811 1975 27.61705 1980 27.32013 1985 27.05795 1990 26.89956 1995 26.85759 2000 26.89462 2005 26.83509 2010 26.65861 2015 26.57081 2020 26.70757 2025 27.29444 2030 28.29632 2035 29.45974 2040 30.48181 2045 31.20796 2050 31.65779 2055 31.89763 2060 32.03596 2065 31.99783 2070 31.75496 2075 31.34533 2080 30.81727 2085 30.2728 2090 29.70127 2095 29.09613 2100 28.46212