Year Percent 1950 8.11122 1955 7.44137 1960 6.82472 1965 6.56142 1970 6.75018 1975 7.1032 1980 7.69275 1985 8.01441 1990 9.01616 1995 9.76411 2000 10.5991 2005 11.47138 2010 13.17829 2015 16.14627 2020 18.54096 2025 22.03221 2030 26.61187 2035 30.29245 2040 32.02911 2045 33.81034 2050 37.19085 2055 38.34366 2060 37.96872 2065 37.44721 2070 37.28119 2075 37.57612 2080 37.73853 2085 37.62145 2090 37.46817 2095 37.48848 2100 37.69441