Year Percent 1950 13.54988 1955 13.91048 1960 14.13767 1965 15.09751 1970 15.53026 1975 14.86841 1980 13.48404 1985 14.15106 1990 14.11071 1995 11.57635 2000 11.56661 2005 9.63121 2010 6.72805 2015 5.64764 2020 5.77669 2025 5.54695 2030 5.01875 2035 4.41453 2040 4.05521 2045 3.99 2050 4.06088 2055 4.07302 2060 3.94484 2065 3.74796 2070 3.60844 2075 3.60369 2080 3.70685 2085 3.83235 2090 3.89972 2095 3.90222 2100 3.89604