Year Percent 1950 5.45026 1955 5.62526 1960 5.73389 1965 6.14964 1970 7.12114 1975 8.09839 1980 7.79147 1985 7.87264 1990 10.97901 1995 11.95494 2000 13.71617 2005 12.55308 2010 13.37862 2015 15.37731 2020 17.38822 2025 19.0507 2030 18.99921 2035 19.68216 2040 20.53825 2045 22.18054 2050 24.24896 2055 24.26224 2060 22.89455 2065 22.17737 2070 22.31899 2075 23.66132 2080 24.8741 2085 25.77441 2090 26.18206 2095 26.38119 2100 26.79669