Year Percent 1950 16.17168 1955 21.05598 1960 19.77652 1965 18.58284 1970 17.9998 1975 18.23667 1980 17.03313 1985 17.40617 1990 16.27437 1995 15.32219 2000 15.1097 2005 13.59699 2010 11.9769 2015 11.15708 2020 10.74653 2025 10.14043 2030 9.36416 2035 8.60032 2040 7.99469 2045 7.55831 2050 7.22597 2055 6.90996 2060 6.60377 2065 6.31521 2070 6.08376 2075 5.91414 2080 5.78451 2085 5.67729 2090 5.56624 2095 5.45455 2100 5.35558