Year Percent 1950 15.98336 1955 16.0217 1960 15.65198 1965 15.4334 1970 15.2648 1975 15.39849 1980 15.6328 1985 15.58372 1990 15.67061 1995 16.42542 2000 17.29794 2005 18.44261 2010 19.61763 2015 20.65367 2020 21.78632 2025 23.17157 2030 24.54126 2035 25.62027 2040 26.4827 2045 26.94305 2050 27.11512 2055 26.88483 2060 26.61073 2065 26.29146 2070 26.00631 2075 25.96047 2080 25.72376 2085 25.37682 2090 25.00023 2095 24.68869 2100 24.45844