Year	Ratio
1972-01-01	0.505129992961884
1973-01-01	0.407290011644363
1975-01-01	0.400389999151230
1976-01-01	0.398550003767014
1977-01-01	0.400160014629364
1978-01-01	0.394160002470016
1979-01-01	0.415950000286102
1980-01-01	0.443170011043549
1981-01-01	0.418260008096695
1982-01-01	0.436560004949570
1983-01-01	0.455570012331009
1984-01-01	0.465229988098145
1985-01-01	0.489389985799789
1986-01-01	0.508260011672974
1987-01-01	0.525129973888397
1988-01-01	0.554629981517792
1989-01-01	0.560620009899139
1990-01-01	0.578649997711182
1991-01-01	0.605669975280762
1993-01-01	0.599669992923737
1994-01-01	0.652639985084534
1995-01-01	0.675419986248016
1996-01-01	0.674769997596741
1999-01-01	0.698700010776520
2000-01-01	0.744970023632050
2001-01-01	0.767989993095398
2002-01-01	0.767650008201599
2004-01-01	0.798789978027344
2005-01-01	0.803879976272583
2006-01-01	0.829980015754700
2007-01-01	0.822250008583069
2008-01-01	0.835789978504181
2009-01-01	0.863049983978271
2010-01-01	0.895179986953735
2011-01-01	0.901189982891083
2012-01-01	0.886330008506775
2013-01-01	0.896809995174408
2014-01-01	0.905730009078979
2015-01-01	0.917530000209808
2016-01-01	0.892549991607666