Year Percent 1950 29.75827 1955 27.85787 1960 27.29707 1965 26.81289 1970 28.94768 1975 31.50943 1980 32.41809 1985 32.90531 1990 30.44262 1995 27.862 2000 26.34397 2005 25.22866 2010 24.61869 2015 25.26535 2020 24.71585 2025 23.83215 2030 23.50604 2035 22.91891 2040 23.09704 2045 23.40921 2050 23.29946 2055 23.1142 2060 22.80725 2065 22.53759 2070 22.38662 2075 22.313 2080 22.21176 2085 22.01675 2090 21.77085 2095 21.53336 2100 21.33095