Year Percent 1950 27.99017 1955 27.26895 1960 26.40796 1965 25.8565 1970 24.75615 1975 25.48083 1980 26.37026 1985 26.48042 1990 27.10015 1995 27.99251 2000 29.32206 2005 31.47639 2010 33.50826 2015 34.68713 2020 34.84303 2025 33.92269 2030 32.86119 2035 31.65033 2040 30.36306 2045 29.0158 2050 27.4226 2055 25.89851 2060 24.55445 2065 23.48665 2070 22.64514 2075 21.99037 2080 21.44887 2085 21.01015 2090 20.66897 2095 20.4142 2100 20.25368