Year Percent 1950 29.61864 1955 29.9145 1960 30.05892 1965 30.06953 1970 29.67636 1975 28.20057 1980 26.73401 1985 25.62796 1990 25.35175 1995 26.27449 2000 27.37982 2005 28.38265 2010 28.96356 2015 29.34638 2020 29.93825 2025 30.7823 2030 31.93232 2035 32.79484 2040 33.25633 2045 33.2926 2050 32.98636 2055 32.64213 2060 32.21494 2065 31.69482 2070 31.12764 2075 30.5655 2080 30.00687 2085 29.48234 2090 28.977 2095 28.48714 2100 28.03503