Year Percent 1950 12.05404 1955 11.5365 1960 10.31929 1965 13.33806 1970 13.82086 1975 12.80201 1980 12.52522 1985 12.89846 1990 13.08674 1995 13.19837 2000 12.59483 2005 11.60733 2010 10.49601 2015 9.48195 2020 8.95762 2025 8.29239 2030 7.70356 2035 7.07423 2040 6.53188 2045 6.08298 2050 5.73489 2055 5.44559 2060 5.19671 2065 4.9879 2070 4.80702 2075 4.67884 2080 4.58554 2085 4.51687 2090 4.47357 2095 4.43493 2100 4.40498