Year Percent 1950 12.99228 1955 13.69479 1960 14.31308 1965 14.22444 1970 14.3324 1975 13.37996 1980 12.46138 1985 12.38971 1990 12.21473 1995 10.99886 2000 9.93547 2005 9.35513 2010 8.32285 2015 7.34712 2020 6.94227 2025 6.46918 2030 6.01049 2035 5.61818 2040 5.3119 2045 5.06942 2050 4.88441 2055 4.75835 2060 4.64901 2065 4.56075 2070 4.5008 2075 4.46579 2080 4.45907 2085 4.46804 2090 4.47713 2095 4.4827 2100 4.49198