Year Percent 1950 10.7257 1955 10.77809 1960 11.62446 1965 12.19704 1970 12.75702 1975 13.369 1980 13.70379 1985 13.88456 1990 14.75746 1995 16.04285 2000 17.69785 2005 21.64399 2010 21.62219 2015 21.87863 2020 22.10679 2025 22.68552 2030 23.19035 2035 23.93047 2040 23.76355 2045 23.44671 2050 24.28686 2055 24.99416 2060 25.70976 2065 25.98136 2070 25.5288 2075 25.12856 2080 24.98135 2085 24.94567 2090 24.8331 2095 24.56563 2100 24.22719