Year Percent 1950 26.72507 1955 24.69246 1960 24.38029 1965 23.55625 1970 21.48174 1975 20.97973 1980 22.2915 1985 24.99128 1990 28.73949 1995 28.84607 2000 28.73246 2005 28.05589 2010 27.08145 2015 26.4793 2020 27.17149 2025 28.36057 2030 30.70078 2035 31.3489 2040 30.72627 2045 29.92069 2050 28.39779 2055 27.92979 2060 28.22829 2065 28.35036 2070 27.83366 2075 26.69983 2080 25.51747 2085 24.77252 2090 24.53144 2095 24.45851 2100 24.13932