Year Percent 1950 22.94385 1955 22.94235 1960 22.98702 1965 22.70316 1970 22.26956 1975 21.26738 1980 20.16415 1985 19.93037 1990 21.28294 1995 23.52147 2000 26.09372 2005 27.83481 2010 27.62683 2015 26.4494 2020 24.87106 2025 23.82903 2030 23.80687 2035 24.42603 2040 24.8376 2045 24.93373 2050 24.7284 2055 23.99652 2060 23.67203 2065 23.54466 2070 23.41686 2075 23.5138 2080 23.41298 2085 23.16258 2090 22.91574 2095 22.76918 2100 22.71139