Year Percent 1950 6.79982 1955 6.78791 1960 7.26105 1965 8.02477 1970 8.5777 1975 9.07744 1980 9.44051 1985 9.61255 1990 11.40778 1995 11.86773 2000 12.9393 2005 14.31774 2010 16.06573 2015 18.27676 2020 20.41245 2025 24.96689 2030 29.36473 2035 33.09282 2040 34.09024 2045 34.88192 2050 36.6319 2055 37.49191 2060 37.88301 2065 37.6822 2070 37.36966 2075 37.69693 2080 38.0893 2085 38.39891 2090 38.5394 2095 38.6347 2100 38.77605