Year Percent 1950 14.56775 1955 14.98832 1960 15.59576 1965 16.89686 1970 18.00858 1975 18.51151 1980 16.9414 1985 17.34705 1990 21.89327 1995 23.54042 2000 25.67182 2005 27.13799 2010 28.51996 2015 30.54775 2020 32.74183 2025 34.65118 2030 35.62062 2035 36.88961 2040 37.64387 2045 38.50696 2050 39.77561 2055 39.89113 2060 37.85108 2065 36.68669 2070 37.00186 2075 37.1979 2080 37.27567 2085 37.28728 2090 37.13342 2095 37.00604 2100 37.18918