Year	Ratio
1972-01-01	0.796060025691986
1974-01-01	1.033740043640140
1975-01-01	1.153579950332640
1977-01-01	1.060359954833980
1978-01-01	0.724389970302582
1992-01-01	0.983060002326965
2000-01-01	0.903859972953796
2007-01-01	0.963949978351593
2008-01-01	0.939310014247894
2009-01-01	0.995239973068237
2010-01-01	1.012390017509460
2011-01-01	0.993799984455109
2012-01-01	1.152619957923890
2014-01-01	1.009430050849910
2015-01-01	1.020920038223270