Year Percent 1950 16.26743 1955 16.18457 1960 16.6358 1965 16.94973 1970 17.08068 1975 17.32026 1980 17.19379 1985 16.75821 1990 15.90404 1995 14.99155 2000 14.57854 2005 13.18478 2010 12.64511 2015 12.87944 2020 12.47287 2025 11.70999 2030 10.91701 2035 10.33608 2040 9.84795 2045 9.35815 2050 8.82187 2055 8.30772 2060 7.83917 2065 7.41587 2070 7.07483 2075 6.77913 2080 6.50931 2085 6.27168 2090 6.05822 2095 5.87884 2100 5.72601