Year Percent 1950 27.58068 1955 27.84208 1960 27.75974 1965 27.47551 1970 27.32562 1975 26.48566 1980 26.32286 1985 26.75546 1990 27.47217 1995 28.85042 2000 29.54187 2005 30.29908 2010 31.0644 2015 30.98018 2020 30.6812 2025 30.23223 2030 30.37147 2035 30.92998 2040 31.17694 2045 31.20363 2050 30.86407 2055 30.29044 2060 29.91258 2065 29.71048 2070 29.52021 2075 29.19363 2080 28.74168 2085 28.22809 2090 27.7428 2095 27.31537 2100 26.9081