Year Ratio 1971-01-01 0.973110020160675 1972-01-01 0.997169971466064 1973-01-01 1.011710047721860 1974-01-01 0.842779994010925 1975-01-01 0.921679973602295 1976-01-01 0.998510003089905 1977-01-01 0.977729976177216 1978-01-01 0.972000002861023 1979-01-01 0.973940014839172 1980-01-01 0.987190008163452 1981-01-01 0.997799992561340 1982-01-01 0.968559980392456 1983-01-01 0.941600024700165 1984-01-01 0.998099982738495 1985-01-01 0.959529995918274 1989-01-01 1.008129954338070 1990-01-01 0.992429971694946 1992-01-01 1.001579999923710 1999-01-01 0.983600020408630 2000-01-01 0.981050014495850 2001-01-01 0.988740026950836 2002-01-01 0.990840017795563 2003-01-01 0.980009973049164 2004-01-01 0.980199992656708 2005-01-01 0.996110022068024 2006-01-01 0.980379998683929 2007-01-01 1.006819963455200 2008-01-01 1.001899957656860 2009-01-01 1.007580041885380 2010-01-01 1.016680002212520 2011-01-01 1.000540018081670 2014-01-01 1.011190056800840 2015-01-01 1.004430055618290 2016-01-01 1.013700008392330