Year	Ratio
1971-01-01	0.531180024147034
1972-01-01	0.544350028038025
1973-01-01	0.563279986381531
1974-01-01	0.574090003967285
1975-01-01	0.579779982566834
1976-01-01	0.584879994392395
1977-01-01	0.586409986019135
1978-01-01	0.592419981956482
1979-01-01	0.598699986934662
1980-01-01	0.602840006351471
1981-01-01	0.612789988517761
1982-01-01	0.622479975223541
1983-01-01	0.631429970264435
1984-01-01	0.628899991512299
1985-01-01	0.635980010032654
1986-01-01	0.643920004367828
1987-01-01	0.648180007934570
1988-01-01	0.655219972133636
1989-01-01	0.663460016250610
1990-01-01	0.677209973335266
1991-01-01	0.688260018825531
1992-01-01	0.698210000991821
1993-01-01	0.708570003509521
1994-01-01	0.725040018558502
1995-01-01	0.739679992198944
1996-01-01	0.753949999809265
1997-01-01	0.766820013523102
1998-01-01	0.786909997463226
1999-01-01	0.820620000362396
2000-01-01	0.849699974060059
2001-01-01	0.878620028495789
2002-01-01	0.896730005741119
2003-01-01	0.907829999923706
2004-01-01	0.910359978675842
2005-01-01	0.907239973545074
2006-01-01	0.905730009078979
2007-01-01	0.911210000514984
2008-01-01	0.919229984283447
2009-01-01	0.932020008563995
2010-01-01	0.940980017185211
2011-01-01	0.948520004749298
2012-01-01	0.953339993953705
2013-01-01	0.955280005931854
2014-01-01	0.954309999942780
2015-01-01	0.946919977664948
2016-01-01	0.949649989604950