Year	Ratio
1974-01-01	0.469689995050430
1975-01-01	0.538739979267120
1976-01-01	0.511399984359741
1977-01-01	0.521120011806488
1978-01-01	0.432709991931915
1979-01-01	0.336140006780624
1980-01-01	0.335960000753403
1994-01-01	0.527700006961823
2003-01-01	0.826900005340576
2004-01-01	0.885510027408600
2005-01-01	0.903479993343353
2006-01-01	0.944570004940033
2007-01-01	0.978139996528625
2008-01-01	1.016829967498780
2009-01-01	1.039000034332280
2010-01-01	1.063889980316160
2011-01-01	1.091259956359860
2012-01-01	1.110499978065490
2013-01-01	1.135920047760010
2014-01-01	1.163149952888490
2015-01-01	1.187809944152830
2016-01-01	1.206269979476930