Year Percent 1950 3.72831 1955 3.56788 1960 4.819 1965 5.22119 1970 5.6018 1975 6.10905 1980 6.51669 1985 6.75711 1990 9.46822 1995 9.83418 2000 9.55126 2005 9.06934 2010 11.30202 2015 12.30821 2020 14.03699 2025 16.68056 2030 19.46288 2035 21.869 2040 24.39678 2045 27.06937 2050 29.5547 2055 33.19704 2060 36.3405 2065 38.23579 2070 39.0396 2075 39.69578 2080 40.16454 2085 40.38045 2090 40.39704 2095 40.26493 2100 40.06215