Year	Ratio
1971-01-01	0.511099994182587
1972-01-01	0.504710018634796
1978-01-01	0.831830024719238
1981-01-01	1.028169989585880
1983-01-01	0.955139994621277
1984-01-01	0.906840026378632
1985-01-01	0.857479989528656
1986-01-01	0.873920023441315
1987-01-01	0.952530026435852
1988-01-01	1.030719995498660
1989-01-01	1.070399999618530
1990-01-01	1.113160014152530
1991-01-01	1.110440015792850
1992-01-01	1.109570026397710
1993-01-01	1.027870059013370
1994-01-01	1.114400029182430
1995-01-01	1.075979948043820
1996-01-01	1.129259943962100
1997-01-01	1.263779997825620
1998-01-01	1.271289944648740
1999-01-01	1.438249945640560
2000-01-01	1.426450014114380
2001-01-01	1.493469953536990
2002-01-01	1.535609960556030
2003-01-01	1.556699991226200
2004-01-01	1.527300000190730
2005-01-01	1.424589991569520
2006-01-01	1.317459940910340
2007-01-01	1.351179957389830
2008-01-01	1.296329975128170
2009-01-01	1.347129940986630
2010-01-01	1.337960004806520
2011-01-01	1.354820013046260
2012-01-01	1.402099967002870
2013-01-01	1.457640051841740
2014-01-01	1.520720005035400
2015-01-01	1.530509948730470
2016-01-01	1.578199982643130