Year Percent 1950 9.1024 1955 7.76542 1960 7.25333 1965 6.91062 1970 6.68211 1975 6.64635 1980 5.95234 1985 5.85875 1990 7.93424 1995 8.61446 2000 9.27688 2005 8.52096 2010 8.11486 2015 9.27386 2020 11.68786 2025 14.81914 2030 17.03631 2035 18.52224 2040 19.83008 2045 21.9853 2050 24.74199 2055 26.87508 2060 27.5014 2065 27.35153 2070 27.63186 2075 29.33635 2080 30.59392 2085 31.18198 2090 31.49536 2095 31.98131 2100 32.64029