Year Percent 1950 8.48083 1955 8.80085 1960 9.96929 1965 11.65851 1970 13.38194 1975 14.41186 1980 13.48311 1985 13.85867 1990 17.3854 1995 18.41679 2000 19.36818 2005 20.00409 2010 22.4401 2015 25.74925 2020 29.02439 2025 30.81395 2030 32.17304 2035 34.23746 2040 37.06888 2045 40.24858 2050 42.47915 2055 44.01864 2060 44.4239 2065 44.16918 2070 44.54572 2075 44.5864 2080 44.15881 2085 43.47729 2090 42.84001 2095 42.36197 2100 42.18814