Year Percent 1950 23.91805 1955 21.9791 1960 23.87839 1965 24.87832 1970 25.07991 1975 24.93647 1980 24.76224 1985 25.08941 1990 26.07269 1995 27.35368 2000 28.44333 2005 27.56448 2010 26.76193 2015 26.06235 2020 26.73817 2025 28.96086 2030 31.78841 2035 33.29214 2040 32.92546 2045 31.997 2050 30.7121 2055 30.04724 2060 29.69427 2065 29.27286 2070 28.57594 2075 27.64058 2080 26.63887 2085 25.70707 2090 24.92315 2095 24.2429 2100 23.60372