Year Percent 1950 13.44573 1955 13.73158 1960 15.55508 1965 15.31713 1970 14.90462 1975 14.96356 1980 15.34013 1985 15.75217 1990 15.81325 1995 15.10999 2000 15.25141 2005 14.72884 2010 13.98945 2015 12.3597 2020 11.48444 2025 10.88176 2030 10.23335 2035 9.55842 2040 8.89752 2045 8.29803 2050 7.76713 2055 7.30746 2060 6.90327 2065 6.55312 2070 6.22844 2075 5.95353 2080 5.71802 2085 5.53319 2090 5.37746 2095 5.25068 2100 5.13785