Year Ratio 1971-01-01 0.770680010318756 1972-01-01 0.769060015678406 1973-01-01 0.795029997825623 1974-01-01 0.794820010662079 1975-01-01 0.814549982547760 1976-01-01 0.834990024566650 1977-01-01 0.855830013751984 1978-01-01 0.874909996986389 1979-01-01 0.887499988079071 1980-01-01 0.908800005912781 1981-01-01 0.919910013675690 1982-01-01 0.924160003662109 1983-01-01 0.934660017490387 1984-01-01 0.939429998397827 1985-01-01 0.945529997348785 1986-01-01 0.956359982490540 1987-01-01 0.969460010528564 1988-01-01 0.975210011005402 1989-01-01 0.981119990348816 1990-01-01 0.988529980182648 1991-01-01 0.992359995841980 1992-01-01 0.977169990539551 1997-01-01 0.974500000476837 1998-01-01 0.971329987049103 1999-01-01 0.981949985027313 2000-01-01 0.975960016250610 2001-01-01 0.994499981403351 2002-01-01 0.988759994506836 2003-01-01 0.984399974346161 2004-01-01 0.992590010166168 2005-01-01 1.007109999656680 2006-01-01 1.033179998397830 2007-01-01 1.024710059165950 2008-01-01 1.030009984970090 2009-01-01 1.028839945793150 2010-01-01 1.025709986686710 2011-01-01 1.029320001602170 2012-01-01 1.021170020103450 2013-01-01 1.022220015525820 2014-01-01 1.022699952125550 2015-01-01 1.011409997940060 2016-01-01 0.996410012245178