Year	Ratio
1970-01-01	0.80399
1971-01-01	0.80448
1972-01-01	0.80834
1973-01-01	0.80346
1974-01-01	0.80277
1975-01-01	0.80115
1976-01-01	0.79808
1977-01-01	0.80793
1978-01-01	0.80819
1979-01-01	0.80352
1980-01-01	0.79994
1981-01-01	0.78774
1982-01-01	0.80257
1983-01-01	0.79681
1984-01-01	0.79737
1985-01-01	0.79854
1986-01-01	0.78204
1987-01-01	0.77810
1988-01-01	0.79403
1989-01-01	0.79961
1990-01-01	0.80407
1991-01-01	0.81540
1992-01-01	0.82714
1993-01-01	0.83888
1994-01-01	0.83998
1995-01-01	0.85195
1996-01-01	0.85249
1997-01-01	0.87261
1998-01-01	0.89076
1999-01-01	0.91523
2000-01-01	0.92836
2001-01-01	0.93257
2002-01-01	0.95995
2003-01-01	0.95945
2004-01-01	0.97198
2005-01-01	0.98910
2006-01-01	1.01250
2007-01-01	1.02086
2008-01-01	1.02971
2009-01-01	1.03254
2010-01-01	1.03465
2011-01-01	1.03702
2012-01-01	1.06625
2013-01-01	1.08813
2014-01-01	1.10402
2015-01-01	1.10759
2016-01-01	1.11805