Year Percent 1950 6.79785 1955 6.33363 1960 6.01945 1965 5.64347 1970 5.15025 1975 4.63577 1980 4.21853 1985 3.92649 1990 4.26013 1995 4.29814 2000 4.2022 2005 4.0123 2010 4.12007 2015 4.4954 2020 4.94721 2025 5.47598 2030 6.13773 2035 7.08986 2040 8.35813 2045 9.84814 2050 11.33252 2055 12.58675 2060 14.07652 2065 15.70079 2070 17.4378 2075 18.99912 2080 20.52628 2085 22.0397 2090 23.5573 2095 25.05135 2100 26.48371