Year	Ratio
1970-01-01	0.0355800017714500
1971-01-01	0.0818499997258186
1972-01-01	0.0838399976491928
1974-01-01	0.1098200008273120
1977-01-01	0.1898600012063980
1983-01-01	0.2093099951744080
1984-01-01	0.2154799997806550
1998-01-01	0.7583500146865840
1999-01-01	0.7744200229644780
2000-01-01	0.7958999872207640
2001-01-01	0.8308899998664860
2005-01-01	0.8926299810409550
2006-01-01	0.9210100173950200
2007-01-01	0.9397699832916260
2008-01-01	0.9521099925041200
2009-01-01	1.0041300058364900
2010-01-01	1.0196800231933600
2011-01-01	1.0468200445175200
2012-01-01	1.0624300241470300
2013-01-01	1.0740599632263200
2014-01-01	1.0729999542236300
2015-01-01	1.0647000074386600
2016-01-01	1.0951800346374500