Year Percent 1950 9.38472 1955 10.97404 1960 10.84713 1965 11.31113 1970 10.96903 1975 10.04915 1980 9.58488 1985 8.06226 1990 7.7649 1995 8.09132 2000 8.20572 2005 7.39579 2010 6.84908 2015 7.16777 2020 6.77357 2025 6.57719 2030 6.39165 2035 6.17055 2040 5.94213 2045 5.79214 2050 5.7112 2055 5.63252 2060 5.548 2065 5.44123 2070 5.32911 2075 5.23472 2080 5.16882 2085 5.12022 2090 5.07879 2095 5.02885 2100 4.97412