Year Percent 1950 5.04949 1955 4.89682 1960 5.40709 1965 5.72471 1970 6.02494 1975 6.52509 1980 6.01379 1985 6.01717 1990 7.26502 1995 8.28287 2000 8.95578 2005 9.55611 2010 10.35777 2015 11.47742 2020 12.90613 2025 14.90707 2030 17.01024 2035 19.3623 2040 21.9143 2045 24.42277 2050 26.59116 2055 28.47952 2060 30.40983 2065 32.07784 2070 33.50781 2075 34.83733 2080 35.95363 2085 36.84444 2090 37.53093 2095 38.10935 2100 38.59649