Year Percent 1950 12.51728 1955 12.08848 1960 11.7782 1965 12.7673 1970 13.88064 1975 15.31572 1980 14.8866 1985 15.7225 1990 20.5988 1995 21.64942 2000 23.32785 2005 22.72067 2010 23.27805 2015 24.75762 2020 27.22685 2025 29.47156 2030 30.77267 2035 32.10214 2040 33.28432 2045 34.80253 2050 36.3163 2055 36.41716 2060 35.21891 2065 34.003 2070 33.57568 2075 33.90816 2080 34.1918 2085 34.34469 2090 34.32113 2095 34.33647 2100 34.61641