Year Percent 1950 9.05693 1955 8.13468 1960 8.87173 1965 9.49682 1970 9.32952 1975 8.1794 1980 7.87919 1985 7.35429 1990 7.59936 1995 7.67192 2000 6.91512 2005 5.32248 2010 4.5023 2015 4.73481 2020 5.27973 2025 5.39639 2030 5.50249 2035 5.24896 2040 4.88006 2045 4.80787 2050 5.04778 2055 5.31316 2060 5.41472 2065 5.3171 2070 5.12275 2075 5.0189 2080 5.08987 2085 5.2399 2090 5.3191 2095 5.25806 2100 5.12242