Year Percent 1950 3.53622 1955 3.52368 1960 3.80582 1965 3.71346 1970 3.77697 1975 4.10895 1980 4.42459 1985 4.89315 1990 6.44308 1995 7.21598 2000 7.23905 2005 7.7708 2010 8.08949 2015 9.04139 2020 10.41409 2025 12.07186 2030 13.71612 2035 14.86719 2040 15.63699 2045 15.93672 2050 15.92245 2055 16.65982 2060 17.79376 2065 19.32095 2070 21.70925 2075 23.67446 2080 25.1297 2085 26.48635 2090 27.96171 2095 29.68663 2100 31.48442