Year	Ratio
1971-01-01	0.769209980964661
1972-01-01	0.744369983673096
1973-01-01	0.751489996910095
1974-01-01	0.859120011329651
1975-01-01	0.879719972610474
1976-01-01	0.703540027141571
1977-01-01	0.753639996051788
1978-01-01	0.822560012340546
1979-01-01	0.872370004653931
1980-01-01	0.869300007820129
1985-01-01	1.139050006866460
1986-01-01	1.141049981117250
1987-01-01	1.128360033035280
1988-01-01	1.147729992866520
1989-01-01	1.168879985809330
1990-01-01	1.188609957695010
1991-01-01	1.222589969635010
1992-01-01	1.230550050735470
1993-01-01	1.244560003280640
1994-01-01	1.250890016555790
1995-01-01	1.264940023422240
1996-01-01	1.285719990730290
1997-01-01	1.313030004501340
1998-01-01	1.337080001831050
1999-01-01	1.412330031394960
2000-01-01	1.450430035591130
2001-01-01	1.503239989280700
2002-01-01	1.532109975814820
2003-01-01	1.541869997978210
2004-01-01	1.540130019187930
2005-01-01	1.543169975280760
2006-01-01	1.542549967765810
2007-01-01	1.568959951400760
2008-01-01	1.594190001487730
2009-01-01	1.581859946250920
2010-01-01	1.531780004501340
2011-01-01	1.511970043182370
2012-01-01	1.552549958229060
2013-01-01	1.554780006408690
2014-01-01	1.537240028381350
2015-01-01	1.525189995765690