Year	Ratio
1971-01-01	0.934970021247864
1972-01-01	0.939689993858337
1973-01-01	0.947480022907257
1974-01-01	0.983099997043610
1975-01-01	0.992990016937256
1976-01-01	0.980319976806641
1977-01-01	0.990040004253387
1978-01-01	0.968959987163544
1979-01-01	0.987770020961761
1980-01-01	1.016219973564150
1981-01-01	0.776589989662170
1982-01-01	0.947449982166290
1983-01-01	0.923539996147156
1984-01-01	0.920369982719421
1986-01-01	0.984130024909973
1987-01-01	0.990869998931885
1988-01-01	1.017670035362240
1992-01-01	1.025539994239810
1993-01-01	1.050240039825440
1994-01-01	1.039330005645750
1995-01-01	1.009529948234560
1996-01-01	1.038810014724730
1997-01-01	1.065209984779360
1998-01-01	1.050410032272340
1999-01-01	1.044379949569700
2000-01-01	1.058359980583190
2001-01-01	1.066380023956300
2002-01-01	1.064270019531250
2003-01-01	1.053990006446840
2004-01-01	1.049739956855770
2005-01-01	1.054059982299800
2006-01-01	1.037619948387150
2007-01-01	1.032580018043520
2008-01-01	1.025239944458010
2010-01-01	1.029770016670230
2011-01-01	1.031059980392460
2012-01-01	1.035240054130550
2013-01-01	1.026090025901790
2014-01-01	1.023460030555730
2015-01-01	1.038210034370420