Year Percent 1950 17.54171 1955 18.21429 1960 18.77679 1965 19.77314 1970 21.5019 1975 23.08156 1980 24.87943 1985 26.61324 1990 28.68066 1995 29.07787 2000 28.45607 2005 27.4536 2010 26.05255 2015 26.89362 2020 27.6357 2025 27.70349 2030 26.701 2035 24.22586 2040 22.90585 2045 22.01928 2050 21.69971 2055 21.71789 2060 21.6218 2065 21.60163 2070 21.52458 2075 21.45198 2080 21.45091 2085 21.51185 2090 21.54928 2095 21.49664 2100 21.35376