Year Percent 1950 13.81871 1955 12.38798 1960 12.7901 1965 12.79438 1970 11.65065 1975 12.39505 1980 11.47053 1985 9.55262 1990 9.81534 1995 8.09464 2000 9.20697 2005 7.3335 2010 6.7198 2015 7.00915 2020 6.63183 2025 6.16298 2030 5.87306 2035 5.77987 2040 5.71713 2045 5.56226 2050 5.3671 2055 5.1383 2060 4.97795 2065 4.85662 2070 4.73446 2075 4.58732 2080 4.42631 2085 4.27535 2090 4.15512 2095 4.08315 2100 4.03995