Year Percent 1950 13.59532 1955 13.3636 1960 14.37886 1965 14.70617 1970 14.90926 1975 14.55313 1980 14.31173 1985 14.01442 1990 12.84117 1995 11.99774 2000 11.97389 2005 11.34543 2010 9.55128 2015 8.62987 2020 8.05783 2025 7.78471 2030 7.30314 2035 6.73147 2040 6.17764 2045 5.72327 2050 5.40989 2055 5.19587 2060 4.99787 2065 4.78924 2070 4.58272 2075 4.42565 2080 4.32598 2085 4.27873 2090 4.25219 2095 4.22844 2100 4.1917