Year	Ratio
1970-01-01	0.99443
1971-01-01	0.99474
1972-01-01	0.99512
1973-01-01	1.00026
1974-01-01	0.99577
1975-01-01	0.99644
1976-01-01	1.00130
1977-01-01	0.99633
1978-01-01	0.99654
1979-01-01	0.99561
1980-01-01	0.99656
1981-01-01	0.99675
1982-01-01	0.99451
1983-01-01	0.99025
1984-01-01	0.99360
1985-01-01	0.99563
1986-01-01	0.99428
1987-01-01	0.99133
1988-01-01	0.99120
1989-01-01	0.99295
1990-01-01	0.99568
1991-01-01	0.99317
1992-01-01	0.99313
1993-01-01	0.99227
1994-01-01	0.99457
1995-01-01	0.99293
1996-01-01	0.99204
1997-01-01	0.99879
1998-01-01	1.00470
1999-01-01	1.00566
2000-01-01	0.99131
2001-01-01	0.99607
2002-01-01	0.99901
2003-01-01	0.99664
2004-01-01	0.99312
2005-01-01	0.99038
2006-01-01	0.99743
2007-01-01	0.99378
2008-01-01	0.99522
2009-01-01	0.99675
2010-01-01	0.99233
2011-01-01	0.99819
2012-01-01	0.99179
2013-01-01	0.99474