Year Percent 1950 17.66214 1955 18.38408 1960 17.79764 1965 17.42267 1970 16.8726 1975 15.55788 1980 15.83603 1985 16.08768 1990 15.40544 1995 14.26985 2000 13.20015 2005 11.47277 2010 10.8217 2015 10.10068 2020 9.67221 2025 9.08148 2030 8.41551 2035 7.79376 2040 7.2993 2045 6.89298 2050 6.55486 2055 6.2398 2060 5.93898 2065 5.67244 2070 5.45985 2075 5.28777 2080 5.13527 2085 5.01428 2090 4.92322 2095 4.85187 2100 4.78862