Year Percent 1950 20.78892 1955 22.1192 1960 21.01314 1965 20.80739 1970 18.98901 1975 17.31167 1980 16.65908 1985 15.89088 1990 17.25972 1995 19.43289 2000 20.52188 2005 21.03331 2010 20.85822 2015 20.51142 2020 21.10494 2025 21.56963 2030 21.77172 2035 21.42139 2040 21.22809 2045 21.32161 2050 21.87873 2055 22.92669 2060 23.43451 2065 23.62226 2070 23.46603 2075 23.02949 2080 22.97457 2085 23.158 2090 23.34749 2095 23.35276 2100 23.13531