Year Percent 1950 5.70062 1955 5.35332 1960 5.0822 1965 4.40258 1970 3.84887 1975 4.08215 1980 2.62872 1985 2.01345 1990 2.35483 1995 2.5318 2000 2.85201 2005 2.40717 2010 2.40191 2015 2.52158 2020 3.40878 2025 4.97553 2030 7.16155 2035 9.02237 2040 11.14975 2045 14.92379 2050 19.06133 2055 21.95564 2060 23.74206 2065 25.31777 2070 26.55895 2075 27.87093 2080 29.11884 2085 30.2101 2090 31.14374 2095 31.86414 2100 32.47642