Year	Ratio
1978-01-01	0.1164399981498720
1979-01-01	0.2011000066995620
1980-01-01	0.0785100013017654
1981-01-01	0.0000000000000000
1982-01-01	0.0856700018048286
1983-01-01	0.0399499982595444
1984-01-01	0.4686500132083890
1985-01-01	0.7305700182914730
1986-01-01	0.6161699891090390
1987-01-01	0.6653599739074710
1988-01-01	0.6877099871635440
1989-01-01	0.8915100097656250
1990-01-01	0.9502699971199040
1991-01-01	0.9744899868965150
1992-01-01	1.1853200197219800
1993-01-01	1.2091200351715100
1994-01-01	1.3226300477981600
1995-01-01	1.1756399869918800
1996-01-01	1.0242999792099000
1997-01-01	1.0002100467681900
1998-01-01	0.9407200217247010
2003-01-01	0.7395099997520450
2004-01-01	1.1067399978637700
2005-01-01	1.0657399892807000
2006-01-01	1.0757499933242800
2007-01-01	1.2385100126266500
2009-01-01	1.3918100595474200
2010-01-01	1.4447799921035800
2011-01-01	1.4568099975585900
2013-01-01	1.7851699590683000
2014-01-01	1.9429899454116800
2015-01-01	1.8675199747085600
2016-01-01	1.8214499950408900