Year Percent 1950 15.90057 1955 15.94325 1960 15.77183 1965 15.66539 1970 15.67855 1975 15.95882 1980 15.59518 1985 14.58037 1990 14.74196 1995 14.97325 2000 15.9159 2005 17.01843 2010 17.51071 2015 18.1229 2020 19.27495 2025 20.85091 2030 22.48161 2035 22.93315 2040 22.34429 2045 21.71269 2050 21.29899 2055 22.81706 2060 24.20102 2065 24.90427 2070 25.1682 2075 24.5696 2080 24.59831 2085 24.96805 2090 25.30186 2095 25.28106 2100 24.94757