Year Percent 1950 9.5398 1955 8.8368 1960 9.45962 1965 8.93324 1970 9.30471 1975 9.26492 1980 8.72488 1985 8.54406 1990 8.02413 1995 6.77357 2000 5.67602 2005 5.14817 2010 5.30605 2015 5.09878 2020 4.81744 2025 4.40291 2030 3.93665 2035 3.73784 2040 3.82746 2045 3.97263 2050 4.06222 2055 4.05301 2060 3.98231 2065 3.93504 2070 4.00055 2075 4.1443 2080 4.28655 2085 4.35237 2090 4.348 2095 4.317 2100 4.31632