Year Ratio 1971-01-01 0.977810025215149 1972-01-01 0.973749995231628 1973-01-01 0.979879975318909 1974-01-01 0.981230020523071 1975-01-01 0.993979990482330 1976-01-01 0.995970010757446 1977-01-01 1.014709949493410 1978-01-01 1.020750045776370 1979-01-01 1.020750045776370 1980-01-01 1.030019998550420 1981-01-01 1.035590052604680 1982-01-01 1.029569983482360 1983-01-01 1.039759993553160 1984-01-01 1.024539947509770 1985-01-01 1.026139974594120 1986-01-01 1.015349984169010 1987-01-01 1.012789964675900 1988-01-01 1.010370016098020 1989-01-01 1.011409997940060 1990-01-01 1.015669941902160 1991-01-01 1.015220046043400 1992-01-01 1.014189958572390 1993-01-01 1.066730022430420 1994-01-01 1.068989992141720 1995-01-01 1.082620024681090 1996-01-01 1.079259991645810 1999-01-01 1.080240011215210 2000-01-01 1.106140017509460 2001-01-01 1.114680051803590 2002-01-01 1.122339963912960 2003-01-01 1.103289961814880 2004-01-01 1.098299980163570 2005-01-01 1.119120001792910 2006-01-01 1.127159953117370 2007-01-01 1.133440017700200 2008-01-01 1.146329998970030 2009-01-01 1.150470018386840 2010-01-01 1.139199972152710 2011-01-01 1.136999964714050 2012-01-01 1.139760017395020 2013-01-01 1.136049985885620 2014-01-01 1.133960008621220 2015-01-01 1.136890053749080