Year	Ratio
1971-01-01	0.446260005235672
1972-01-01	0.460260003805161
1973-01-01	0.472050011157990
1974-01-01	0.487870007753372
1975-01-01	0.503300011157990
1976-01-01	0.527530014514923
1977-01-01	0.551540017127991
1978-01-01	0.579869985580444
1979-01-01	0.605560004711151
1980-01-01	0.621320009231567
1981-01-01	0.637139976024628
1982-01-01	0.643530011177063
1983-01-01	0.647740006446838
1984-01-01	0.636500000953674
1985-01-01	0.622929990291595
1986-01-01	0.615520000457764
1987-01-01	0.614260017871857
1988-01-01	0.623250007629395
1989-01-01	0.627460002899170
1990-01-01	0.641860008239746
1991-01-01	0.648320019245148
1992-01-01	0.661119997501373
1994-01-01	0.663160026073456
1995-01-01	0.677630007266998
1996-01-01	0.689119994640350
1997-01-01	0.707180023193359
1998-01-01	0.728079974651337
1999-01-01	0.755649983882904
2000-01-01	0.779160022735596
2001-01-01	0.793810009956360
2002-01-01	0.813970029354095
2003-01-01	0.825890004634857
2004-01-01	0.838980019092560
2005-01-01	0.850109994411469
2006-01-01	0.860729992389679
2007-01-01	0.866110026836395
2008-01-01	0.878459990024567
2009-01-01	0.853619992733002
2010-01-01	0.902339994907379
2011-01-01	0.910160005092621
2012-01-01	0.923669993877411
2013-01-01	0.935790002346039
2014-01-01	0.942480027675629
2015-01-01	0.947309970855713
2016-01-01	0.951669991016388