Year	Ratio
1971-01-01	0.466419994831085
1972-01-01	0.475340008735657
1973-01-01	0.484129995107651
1974-01-01	0.495559990406036
1975-01-01	0.517409980297089
1976-01-01	0.509689986705780
1977-01-01	0.487109988927841
1978-01-01	0.488279998302460
1979-01-01	0.485799998044968
1980-01-01	0.501010000705719
1981-01-01	0.529420018196106
1982-01-01	0.540579974651337
1983-01-01	0.558489978313446
1984-01-01	0.593500018119812
1985-01-01	0.608299970626831
1986-01-01	0.625100016593933
1987-01-01	0.635190010070801
1989-01-01	0.633530020713806
1992-01-01	0.687279999256134
1993-01-01	0.710560023784637
1994-01-01	0.729960024356842
1995-01-01	0.747879981994629
1996-01-01	0.780849993228912
1997-01-01	0.801140010356903
1998-01-01	0.825460016727448
1999-01-01	0.849489986896515
2000-01-01	0.874300003051758
2001-01-01	0.907480001449585
2002-01-01	0.907930016517639
2003-01-01	0.978209972381592
2004-01-01	1.008820056915280
2005-01-01	1.031419992446900
2006-01-01	1.048410058021550
2007-01-01	1.049229979515080
2008-01-01	1.062999963760380
2009-01-01	1.044039964675900
2010-01-01	1.027469992637630
2011-01-01	1.039409995079040
2012-01-01	1.045639991760250
2013-01-01	1.044270038604740
2014-01-01	1.055729985237120
2015-01-01	1.067749977111820
2016-01-01	1.075719952583310
2017-01-01	1.083269953727720