Year Percent 1950 4.89827 1955 4.75964 1960 4.56196 1965 4.38131 1970 4.19177 1975 4.05493 1980 3.8928 1985 3.65275 1990 3.62279 1995 3.74042 2000 3.65067 2005 3.62176 2010 3.86466 2015 4.01362 2020 4.2767 2025 4.61884 2030 5.07469 2035 5.69501 2040 6.56294 2045 7.63199 2050 8.82634 2055 10.33452 2060 12.33347 2065 14.65885 2070 17.1033 2075 19.14926 2080 21.09049 2085 22.85463 2090 24.49135 2095 26.02361 2100 27.44704