Year	Ratio
1981-01-01	1.281909942626950
1986-01-01	1.885779976844790
1989-01-01	0.808059990406036
1990-01-01	0.710560023784637
1992-01-01	1.358839988708500
1993-01-01	1.406030058860780
1994-01-01	1.449650049209590
1995-01-01	1.438480019569400
1996-01-01	1.508849978446960
1997-01-01	1.484809994697570
1998-01-01	1.544360041618350
1999-01-01	1.525449991226200
2000-01-01	1.525089979171750
2001-01-01	1.523920059204100
2002-01-01	1.568590044975280
2003-01-01	1.546169996261600
2004-01-01	1.548269987106320
2005-01-01	1.558789968490600
2006-01-01	1.545850038528440
2007-01-01	1.552279949188230
2008-01-01	1.538300037384030
2009-01-01	1.491809964179990
2010-01-01	1.501170039176940
2011-01-01	1.476549983024600
2012-01-01	1.455189943313600
2013-01-01	1.465440034866330
2014-01-01	1.458570003509520
2015-01-01	1.438249945640560
2016-01-01	1.403519988060000