Year	Ratio
1976-01-01	0.952269971370697
1978-01-01	0.962170004844666
1979-01-01	0.961319983005524
1980-01-01	0.972630023956299
1981-01-01	0.968299984931946
1982-01-01	0.975459992885590
1983-01-01	0.990390002727509
1984-01-01	0.973550021648407
1985-01-01	0.983449995517731
1986-01-01	0.988759994506836
1987-01-01	0.972469985485077
1988-01-01	1.002979993820190
1989-01-01	0.996869981288910
1990-01-01	0.992999970912933
1991-01-01	0.990490019321442
1992-01-01	1.001330018043520
1993-01-01	1.019440054893490
1994-01-01	0.973940014839172
1995-01-01	0.957040011882782
1996-01-01	0.963639974594116
1997-01-01	0.956939995288849
1998-01-01	0.959829986095428
1999-01-01	0.970279991626740
2000-01-01	0.983699977397919
2001-01-01	0.999689996242523
2002-01-01	0.977599978446960
2003-01-01	0.992110013961792
2004-01-01	0.996810019016266
2005-01-01	0.990050017833710
2006-01-01	0.993860006332397
2007-01-01	0.993059992790222
2008-01-01	0.985979974269867
2009-01-01	0.978479981422424
2010-01-01	0.982469975948334
2011-01-01	0.985099971294403
2012-01-01	0.977299988269806
2013-01-01	0.975430011749268
2014-01-01	0.982829988002777
2015-01-01	0.973070025444031
2016-01-01	0.974900007247925