Year Percent 1950 5.12234 1955 4.92718 1960 4.68473 1965 4.51204 1970 4.41214 1975 4.33107 1980 4.26982 1985 4.23998 1990 4.58049 1995 4.70748 2000 4.7637 2005 4.85297 2010 5.10392 2015 5.37693 2020 5.69044 2025 6.0429 2030 6.46207 2035 6.85904 2040 7.29222 2045 7.79131 2050 8.33526 2055 9.157 2060 10.17521 2065 11.27278 2070 12.33986 2075 13.32289 2080 14.26099 2085 15.20959 2090 16.20967 2095 17.25916 2100 18.31704