Year Percent 1950 3.91009 1955 4.01935 1960 4.10353 1965 4.16754 1970 4.221 1975 4.26455 1980 4.30589 1985 4.34022 1990 4.7126 1995 4.76343 2000 4.8432 2005 4.78302 2010 5.00303 2015 5.05619 2020 5.1195 2025 5.22187 2030 5.43251 2035 5.8159 2040 6.38028 2045 7.03616 2050 7.74782 2055 8.50713 2060 9.27519 2065 10.28439 2070 11.3861 2075 12.58757 2080 13.78493 2085 14.99127 2090 16.22837 2095 17.49678 2100 18.77394