Year Percent 1950 25.06145 1955 25.5055 1960 29.35927 1965 30.64826 1970 30.30421 1975 30.55228 1980 30.05432 1985 31.79151 1990 33.73923 1995 32.69107 2000 30.0115 2005 27.1762 2010 24.93177 2015 24.88115 2020 25.1448 2025 24.07156 2030 22.35168 2035 21.26349 2040 20.85464 2045 21.14686 2050 21.62382 2055 21.80284 2060 21.60073 2065 21.20682 2070 20.96284 2075 21.01537 2080 21.24802 2085 21.43067 2090 21.38306 2095 21.12133 2100 20.80754