Year Percent 1950 5.68303 1955 4.51836 1960 4.19162 1965 4.07467 1970 4.09323 1975 4.12796 1980 4.17519 1985 4.28393 1990 4.75009 1995 4.88767 2000 4.99856 2005 5.1302 2010 5.38402 2015 5.89753 2020 6.4383 2025 7.0107 2030 7.6412 2035 8.38145 2040 9.2162 2045 10.05818 2050 10.79248 2055 11.59614 2060 12.63744 2065 13.71501 2070 14.77239 2075 15.73083 2080 16.66134 2085 17.61582 2090 18.59561 2095 19.59892 2100 20.60646