Year Percent 1950 13.94968 1955 13.77805 1960 13.23926 1965 12.69432 1970 12.11359 1975 11.88057 1980 11.84257 1985 12.07389 1990 13.22052 1995 15.10517 2000 17.3608 2005 19.87184 2010 22.0702 2015 23.11534 2020 24.2181 2025 25.23581 2030 26.00327 2035 27.14756 2040 27.54189 2045 27.53614 2050 27.22428 2055 26.66064 2060 26.22128 2065 25.57655 2070 25.01287 2075 24.56336 2080 24.18715 2085 23.92769 2090 23.72679 2095 23.56354 2100 23.415