Year Percent 1950 9.94329 1955 11.37578 1960 11.59449 1965 11.86035 1970 11.21775 1975 9.71936 1980 9.17893 1985 8.64551 1990 8.31036 1995 7.99166 2000 8.19584 2005 7.20289 2010 6.68003 2015 7.0215 2020 6.59328 2025 6.2531 2030 5.99432 2035 5.7091 2040 5.48234 2045 5.36639 2050 5.30339 2055 5.21892 2060 5.10096 2065 4.98789 2070 4.89408 2075 4.83249 2080 4.80169 2085 4.77406 2090 4.73638 2095 4.68596 2100 4.6416