Year Percent 1950 18.064 1955 20.62245 1960 19.76787 1965 20.32612 1970 19.07443 1975 17.26899 1980 15.64957 1985 14.65841 1990 14.208 1995 14.76695 2000 14.6601 2005 14.00719 2010 13.89544 2015 12.50729 2020 11.29839 2025 10.86653 2030 10.7763 2035 10.76355 2040 10.45467 2045 9.78655 2050 8.99244 2055 8.37395 2060 8.06928 2065 7.89592 2070 7.64015 2075 7.20138 2080 6.68453 2085 6.23062 2090 5.94409 2095 5.77171 2100 5.62705