Year Percent 1950 6.13213 1955 4.89126 1960 5.05839 1965 5.32289 1970 6.38608 1975 7.54317 1980 8.98207 1985 9.77347 1990 12.01685 1995 13.50142 2000 14.91589 2005 16.61164 2010 19.59081 2015 23.67556 2020 27.2719 2025 30.93216 2030 33.40477 2035 34.14224 2040 32.93132 2045 31.57543 2050 30.24552 2055 28.61924 2060 29.26998 2065 30.75576 2070 32.88057 2075 33.68942 2080 34.86307 2085 35.66113 2090 36.32986 2095 37.00874 2100 37.59869