Year Percent 1950 13.75503 1955 12.15528 1960 11.22278 1965 10.64241 1970 10.21323 1975 10.33637 1980 10.66517 1985 10.84205 1990 11.01437 1995 10.68659 2000 10.63351 2005 11.40463 2010 12.29616 2015 13.26758 2020 14.32737 2025 15.1774 2030 16.40562 2035 18.20514 2040 19.62602 2045 20.49795 2050 21.1474 2055 21.56528 2060 22.18842 2065 23.01027 2070 23.58251 2075 23.85457 2080 23.96394 2085 24.0755 2090 24.23446 2095 24.38784 2100 24.45089