Year Percent 1950 9.82048 1955 10.31199 1960 10.81113 1965 11.70941 1970 12.44609 1975 12.95874 1980 13.2734 1985 14.30127 1990 18.71037 1995 20.65772 2000 21.43049 2005 21.60361 2010 22.44713 2015 24.44617 2020 26.95629 2025 30.10749 2030 33.44915 2035 37.14683 2040 40.46364 2045 41.86501 2050 41.90395 2055 41.40516 2060 40.57756 2065 40.22607 2070 40.42577 2075 40.2512 2080 40.08001 2085 39.97795 2090 39.99525 2095 40.1618 2100 40.46066