Year Percent 1950 5.44751 1955 5.13057 1960 5.08592 1965 5.17176 1970 6.21622 1975 7.00946 1980 7.30401 1985 7.26543 1990 8.30616 1995 8.68701 2000 9.55966 2005 10.83717 2010 12.43227 2015 14.22007 2020 16.45418 2025 18.95639 2030 20.22598 2035 21.54306 2040 23.21066 2045 26.23636 2050 28.39424 2055 29.0298 2060 28.85056 2065 29.0477 2070 29.83299 2075 30.78706 2080 31.34069 2085 31.53564 2090 31.59132 2095 31.75415 2100 32.12894