Year	Ratio
1971-01-01	0.373580008745193
1972-01-01	0.401380002498627
1973-01-01	0.455509990453720
1974-01-01	0.492170006036758
1975-01-01	0.529980003833771
1976-01-01	0.583109974861145
1977-01-01	0.638480007648468
1978-01-01	0.682659983634949
1979-01-01	0.699580013751984
1980-01-01	0.743239998817444
1981-01-01	0.801110029220581
1982-01-01	0.851949989795685
1983-01-01	0.905870020389557
1984-01-01	0.958700001239777
1985-01-01	0.963029980659485
1986-01-01	1.006489992141720
1987-01-01	1.023200035095210
1988-01-01	1.053470015525820
1989-01-01	1.043920040130620
1990-01-01	1.075099945068360
1991-01-01	1.089650034904480
1992-01-01	1.097970008850100
1993-01-01	1.118330001831050
1994-01-01	1.087589979171750
1995-01-01	1.156640052795410
1996-01-01	1.170910000801090
1997-01-01	1.174630045890810
1998-01-01	1.185619950294490
1999-01-01	1.186239957809450
2000-01-01	1.183899998664860
2001-01-01	1.164860010147090
2002-01-01	1.198189973831180
2003-01-01	1.198359966278080
2004-01-01	1.231899976730350
2005-01-01	1.227229952812190
2006-01-01	1.234349966049190
2007-01-01	1.244029998779300
2008-01-01	1.245049953460690
2009-01-01	1.249240040779110
2010-01-01	1.239220023155210
2011-01-01	1.234709978103640
2012-01-01	1.214949965476990
2013-01-01	1.205690026283260
2014-01-01	1.191329956054690
2015-01-01	1.179980039596560
2016-01-01	1.187479972839360