Year Percent 1950 27.12547 1955 28.04987 1960 27.47151 1965 24.63481 1970 24.72454 1975 25.36868 1980 26.45972 1985 26.43848 1990 26.20388 1995 29.69296 2000 27.16627 2005 28.65847 2010 31.12325 2015 31.15197 2020 31.37176 2025 31.07939 2030 31.20063 2035 32.24532 2040 32.44859 2045 32.01957 2050 31.18758 2055 30.53807 2060 30.12604 2065 29.77005 2070 29.19727 2075 28.33576 2080 27.33543 2085 26.39372 2090 25.61491 2095 24.94058 2100 24.28738