Year Percent 1950 23.50968 1955 24.12171 1960 23.48424 1965 22.80298 1970 23.70155 1975 24.05128 1980 26.81372 1985 26.54425 1990 24.92723 1995 25.22327 2000 25.74996 2005 26.81672 2010 27.5403 2015 28.10611 2020 27.71896 2025 27.5857 2030 28.60527 2035 28.1903 2040 25.90411 2045 23.81259 2050 22.53263 2055 22.47281 2060 24.51183 2065 25.48504 2070 24.51593 2075 23.39801 2080 22.77133 2085 22.80516 2090 23.36323 2095 23.89976 2100 23.85505