Year Percent 1950 14.90187 1955 15.24001 1960 14.1834 1965 13.92067 1970 14.23346 1975 14.30967 1980 14.21771 1985 12.93252 1990 13.06817 1995 13.07952 2000 14.31964 2005 17.05103 2010 18.03933 2015 18.69542 2020 19.50789 2025 21.01087 2030 25.45553 2035 28.09051 2040 28.66208 2045 26.96609 2050 24.57501 2055 24.12638 2060 24.65914 2065 25.41355 2070 24.85739 2075 23.47708 2080 22.2358 2085 21.8192 2090 22.08711 2095 22.3404 2100 22.03581