Year	Ratio
1970-01-01	0.94205
1971-01-01	0.94219
1972-01-01	0.94498
1973-01-01	0.95368
1974-01-01	0.94825
1975-01-01	0.96893
1976-01-01	0.97306
1977-01-01	0.97959
1978-01-01	0.98708
1979-01-01	0.98894
1980-01-01	0.99700
1981-01-01	1.01274
1982-01-01	1.00113
1983-01-01	1.01276
1984-01-01	1.01077
1985-01-01	1.01366
1986-01-01	1.01768
1987-01-01	1.01693
1988-01-01	1.01468
1989-01-01	1.01371
1990-01-01	1.01281
1991-01-01	1.01449
1992-01-01	1.01726
1993-01-01	1.01598
1994-01-01	1.00618
1995-01-01	1.00763
1996-01-01	1.01128
1997-01-01	1.00678
1998-01-01	1.00565
1999-01-01	1.00652
2000-01-01	1.00411
2001-01-01	1.00687
2002-01-01	1.00430
2003-01-01	1.00466
2004-01-01	1.00577
2005-01-01	1.00505
2006-01-01	1.00350
2007-01-01	1.00391
2008-01-01	1.00279
2009-01-01	0.99440
2010-01-01	0.99199
2011-01-01	0.98948
2012-01-01	0.98827
2013-01-01	0.99231
2014-01-01	0.99237
2015-01-01	0.99116
2016-01-01	0.99289