Year	Ratio
1971-01-01	0.861829996109009
1974-01-01	0.932720005512238
1982-01-01	0.937590003013611
1983-01-01	0.917569994926453
1985-01-01	0.921259999275208
1989-01-01	0.993070006370544
1992-01-01	1.002789974212650
1994-01-01	1.004850029945370
1995-01-01	0.994889974594116
1996-01-01	0.991559982299805
1997-01-01	0.972850024700165
1998-01-01	0.968569993972778
1999-01-01	0.969269990921021
2000-01-01	0.971090018749237
2001-01-01	0.986190021038055
2002-01-01	0.955229997634888
2003-01-01	0.939409971237183
2004-01-01	0.926400005817413
2005-01-01	0.918200016021729
2006-01-01	0.913770020008087
2007-01-01	0.913600027561188
2008-01-01	0.914579987525940
2009-01-01	0.919950008392334
2010-01-01	0.912729978561401
2011-01-01	0.907859981060028
2012-01-01	0.912000000476837
2013-01-01	0.912590026855469
2014-01-01	0.915310025215149
2015-01-01	0.914529979228973
2016-01-01	0.913160026073456