Year Percent 1950 8.06258 1955 7.394 1960 10.26378 1965 11.27046 1970 10.24461 1975 8.25414 1980 8.42412 1985 8.3723 1990 8.94816 1995 9.04892 2000 7.26201 2005 5.44218 2010 4.78739 2015 4.9781 2020 5.11015 2025 4.64437 2030 4.18138 2035 3.88347 2040 3.71785 2045 3.76504 2050 3.90012 2055 3.95157 2060 3.88815 2065 3.81596 2070 3.83422 2075 3.97056 2080 4.16875 2085 4.33101 2090 4.387 2095 4.36629 2100 4.35447