Year Percent 1950 13.78633 1955 15.0684 1960 13.86694 1965 14.9397 1970 15.17369 1975 13.65074 1980 11.54574 1985 11.78797 1990 12.04261 1995 11.58508 2000 10.5411 2005 9.45975 2010 8.10389 2015 7.66642 2020 7.09937 2025 6.64277 2030 6.17015 2035 5.78079 2040 5.46618 2045 5.22069 2050 5.05871 2055 4.92599 2060 4.81135 2065 4.70333 2070 4.63189 2075 4.59047 2080 4.57847 2085 4.58351 2090 4.5846 2095 4.58082 2100 4.57366