Year	Ratio
1971-01-01	0.586359977722168
1972-01-01	0.637030005455017
1973-01-01	0.656340003013611
1974-01-01	0.687160015106201
1975-01-01	0.723119974136353
1976-01-01	0.746969997882843
1977-01-01	0.779479980468750
1978-01-01	0.808979988098145
1979-01-01	0.857640027999878
1980-01-01	0.906470000743866
1981-01-01	0.926219999790192
1982-01-01	0.976979970932007
1983-01-01	0.998009979724884
1984-01-01	1.022690057754520
1985-01-01	1.040240049362180
1986-01-01	1.075399994850160
1987-01-01	1.064139962196350
1988-01-01	1.071990013122560
1989-01-01	1.047590017318730
1990-01-01	1.029170036315920
1991-01-01	1.025840044021610
1992-01-01	1.071349978446960
1993-01-01	1.080880045890810
1994-01-01	1.070870041847230
1996-01-01	1.040789961814880
1999-01-01	1.044559955596920
2000-01-01	1.046020030975340
2002-01-01	1.040359973907470
2003-01-01	1.037899971008300
2004-01-01	1.028470039367680
2005-01-01	1.029780030250550
2006-01-01	1.035290002822880
2007-01-01	1.033570051193240
2008-01-01	1.032240033149720
2010-01-01	1.038579940795900
2011-01-01	1.036999940872190
2012-01-01	1.027809977531430
2013-01-01	1.022519946098330
2014-01-01	1.035300016403200