Year Percent 1950 30.92167 1955 27.89406 1960 24.96325 1965 23.73102 1970 25.0233 1975 26.81566 1980 28.95428 1985 30.13466 1990 30.27718 1995 30.02896 2000 28.65416 2005 27.17343 2010 26.48073 2015 26.86323 2020 26.8866 2025 26.40667 2030 25.78947 2035 24.96955 2040 24.49778 2045 24.37678 2050 24.18348 2055 24.1309 2060 23.86766 2065 23.50672 2070 23.16508 2075 22.90468 2080 22.71755 2085 22.54847 2090 22.33837 2095 22.07449 2100 21.8004