Year	Ratio
1991-01-01	0.988009989261627
1992-01-01	0.995819985866547
1993-01-01	0.979700028896332
1994-01-01	0.955860018730164
1995-01-01	1.124429941177370
1996-01-01	1.084290027618410
1997-01-01	0.978860020637512
1998-01-01	0.981549978256226
1999-01-01	1.000630021095280
2000-01-01	0.981610000133514
2001-01-01	0.983919978141785
2002-01-01	0.975650012493134
2003-01-01	0.943490028381348
2004-01-01	0.963519990444183
2005-01-01	0.945110023021698
2006-01-01	0.936280012130737
2007-01-01	0.996879994869232
2008-01-01	0.994690001010895
2009-01-01	0.989229977130890
2010-01-01	0.989530026912689
2011-01-01	0.980520009994507
2012-01-01	0.979770004749298
2013-01-01	0.969030022621155
2014-01-01	0.990019977092743
2015-01-01	0.983179986476898
2016-01-01	0.990109980106354