Year Percent 1950 12.70401 1955 12.603 1960 12.82087 1965 13.58646 1970 14.45683 1975 15.25365 1980 15.4131 1985 15.91821 1990 18.02037 1995 18.16216 2000 18.55553 2005 19.22925 2010 21.05164 2015 22.05899 2020 23.4 2025 25.24681 2030 26.89459 2035 27.83348 2040 28.51799 2045 29.30844 2050 30.15259 2055 30.7702 2060 31.03282 2065 31.09999 2070 31.68998 2075 32.40482 2080 33.08728 2085 33.68565 2090 34.15601 2095 34.60392 2100 35.12925