Year Percent 1950 12.08131 1955 13.02237 1960 14.87694 1965 14.39698 1970 15.36277 1975 14.54366 1980 11.97439 1985 10.47812 1990 9.66631 1995 9.78475 2000 9.20653 2005 8.32509 2010 8.25678 2015 7.62488 2020 7.17891 2025 6.57829 2030 6.25309 2035 6.07604 2040 5.8963 2045 5.66166 2050 5.40554 2055 5.20206 2060 5.06163 2065 4.97619 2070 4.89645 2075 4.80084 2080 4.68594 2085 4.57498 2090 4.49317 2095 4.44078 2100 4.40791