Year	Ratio
1970-01-01	0.99233
1971-01-01	0.99434
1972-01-01	0.99839
1973-01-01	0.99266
1974-01-01	0.98826
1975-01-01	0.98614
1976-01-01	0.99913
1977-01-01	0.99668
1978-01-01	1.00110
1979-01-01	1.00062
1980-01-01	1.00437
1981-01-01	1.00764
1982-01-01	1.00060
1983-01-01	1.00398
1984-01-01	1.00370
1985-01-01	1.00384
1986-01-01	0.99814
1987-01-01	0.98661
1988-01-01	0.99215
1989-01-01	0.99338
1990-01-01	0.99997
1991-01-01	0.99428
1992-01-01	0.98751
1993-01-01	0.98064
1994-01-01	0.98556
1995-01-01	0.98470
1996-01-01	0.98734
1997-01-01	0.98724
1998-01-01	0.98545
1999-01-01	0.98837
2000-01-01	0.98570
2001-01-01	0.98429
2002-01-01	0.98932
2003-01-01	0.98879
2004-01-01	0.98782
2005-01-01	0.98464
2006-01-01	0.98652
2007-01-01	0.98868
2008-01-01	0.98670
2009-01-01	0.98568
2010-01-01	0.98451
2011-01-01	0.98967
2012-01-01	0.99483
2013-01-01	0.98265
2014-01-01	0.98635
2015-01-01	1.01287
2016-01-01	0.98659