Year	Ratio
1970-01-01	0.99117
1971-01-01	0.99195
1972-01-01	0.99216
1973-01-01	0.99628
1974-01-01	0.99075
1975-01-01	0.99043
1976-01-01	0.99465
1977-01-01	0.99129
1978-01-01	0.99342
1979-01-01	0.99393
1980-01-01	0.99618
1981-01-01	0.99682
1982-01-01	0.99395
1983-01-01	0.98916
1984-01-01	0.99153
1985-01-01	0.99309
1986-01-01	0.99195
1987-01-01	0.98817
1988-01-01	0.98686
1989-01-01	0.98720
1990-01-01	0.98888
1991-01-01	0.98581
1992-01-01	0.98658
1993-01-01	0.98665
1994-01-01	0.98939
1995-01-01	0.98851
1996-01-01	0.98788
1997-01-01	0.99383
1998-01-01	0.99991
1999-01-01	1.00104
2000-01-01	0.98851
2001-01-01	0.99396
2002-01-01	0.99677
2003-01-01	0.99525
2004-01-01	0.99282
2005-01-01	0.99119
2006-01-01	0.99752
2007-01-01	0.99388
2008-01-01	0.99521
2009-01-01	0.99675
2010-01-01	0.99386
2011-01-01	0.99969
2012-01-01	0.99487
2013-01-01	0.99679
2014-01-01	0.99823
2015-01-01	1.00148
2016-01-01	0.99995