Year Percent 1950 14.77837 1955 15.33228 1960 15.63553 1965 15.98878 1970 16.67864 1975 17.3824 1980 17.4292 1985 15.57744 1990 13.23051 1995 11.46919 2000 11.8867 2005 13.61803 2010 15.99519 2015 18.28872 2020 20.1038 2025 25.3606 2030 32.9236 2035 37.93626 2040 38.62587 2045 34.36362 2050 27.98182 2055 24.36411 2060 23.88297 2065 24.49523 2070 24.4681 2075 23.31653 2080 22.3636 2085 22.30547 2090 22.97189 2095 23.57943 2100 23.53171