Year Percent 1950 15.19749 1955 15.78843 1960 16.42479 1965 16.88247 1970 17.29003 1975 17.54934 1980 17.27217 1985 16.76955 1990 19.38992 1995 19.25774 2000 19.34039 2005 20.44992 2010 21.65609 2015 23.65808 2020 25.933 2025 28.67781 2030 31.08724 2035 32.7119 2040 33.87889 2045 34.70701 2050 35.13015 2055 35.51874 2060 35.66318 2065 35.72021 2070 35.8824 2075 36.07329 2080 36.31113 2085 36.62248 2090 37.00807 2095 37.44034 2100 37.89864