Year	Ratio
1971-01-01	0.400750011205673
1972-01-01	0.402310013771057
1976-01-01	0.579789996147156
1977-01-01	0.506039977073669
1978-01-01	0.538800001144409
1979-01-01	0.577139973640442
1981-01-01	0.565970003604889
1982-01-01	0.644659996032715
1983-01-01	0.663919985294342
1984-01-01	0.682299971580505
1985-01-01	0.687680006027222
1986-01-01	0.688350021839142
1987-01-01	0.683650016784668
1988-01-01	0.718110024929047
1989-01-01	0.717620015144348
1990-01-01	0.734430015087128
1991-01-01	0.754779994487762
1992-01-01	0.781889975070953
1993-01-01	0.823780000209808
1994-01-01	0.837239980697632
1995-01-01	0.843519985675812
1996-01-01	0.871190011501312
1997-01-01	0.913510024547577
1998-01-01	0.943059980869293
1999-01-01	0.967379987239838
2000-01-01	0.967000007629395
2001-01-01	0.958109974861145
2002-01-01	0.980820000171661
2003-01-01	0.996249973773956
2004-01-01	1.006090044975280
2005-01-01	1.028380036354060
2006-01-01	1.020499944686890
2007-01-01	1.027080059051510
2008-01-01	1.039909958839420
2009-01-01	1.045169949531560
2010-01-01	1.043210029602050
2011-01-01	1.052620053291320
2012-01-01	1.050469994544980
2013-01-01	1.048050045967100
2014-01-01	1.055850028991700
2015-01-01	1.050160050392150
2016-01-01	1.063410043716430