Year Percent 1950 16.79373 1955 15.67841 1960 14.51891 1965 13.30851 1970 12.93902 1975 12.46818 1980 12.39305 1985 12.34223 1990 13.34626 1995 14.67142 2000 16.03843 2005 18.74548 2010 20.19879 2015 21.66335 2020 21.93286 2025 21.32597 2030 19.98137 2035 21.75794 2040 24.15207 2045 26.43714 2050 28.31142 2055 27.7542 2060 27.04473 2065 26.84248 2070 27.26378 2075 27.35245 2080 27.17022 2085 26.94633 2090 26.77644 2095 26.66092 2100 26.54465