Year Percent 1950 13.28433 1955 12.50836 1960 12.341 1965 13.62925 1970 14.63916 1975 15.12694 1980 14.25754 1985 14.89104 1990 19.38048 1995 21.01764 2000 22.97385 2005 25.28005 2010 26.88232 2015 29.25036 2020 31.27427 2025 33.4388 2030 34.79491 2035 36.06715 2040 36.53904 2045 36.68561 2050 37.16732 2055 38.02887 2060 37.76097 2065 36.65757 2070 35.98 2075 36.00366 2080 36.1654 2085 36.48207 2090 36.62892 2095 36.54661 2100 36.51609