Year	Ratio
1970-01-01	1.35116994380951
1971-01-01	1.18245005607605
1972-01-01	1.20453000068665
1973-01-01	1.10021996498108
1975-01-01	1.23618996143341
1976-01-01	1.29581999778748
1977-01-01	1.35281002521515
1978-01-01	1.36924004554749
1979-01-01	1.49571001529694
1980-01-01	1.50987005233765
1981-01-01	1.52148997783661
1982-01-01	1.48281002044678
1983-01-01	1.53685998916626
1984-01-01	1.48573005199432
1985-01-01	1.46138000488281
1986-01-01	1.51356995105743
1987-01-01	1.56907999515533
1988-01-01	1.58283996582031
1989-01-01	1.53586995601654
1990-01-01	1.55034005641937
1991-01-01	1.52075004577637
1992-01-01	1.56089997291565
1993-01-01	1.56177997589111
1994-01-01	1.58588004112244
1996-01-01	1.51510000228882
1997-01-01	1.48517000675201
1998-01-01	1.54102003574371
1999-01-01	1.39262998104095
2000-01-01	1.35237002372742
2001-01-01	1.30281996726990
2002-01-01	1.30841004848480
2003-01-01	1.30092000961304
2004-01-01	1.28737998008728
2005-01-01	1.28966999053955
2006-01-01	1.29228997230530
2007-01-01	1.33975994586945
2008-01-01	1.36494004726410
2009-01-01	1.40162003040314
2010-01-01	1.40918004512787
2011-01-01	1.39736998081207
2012-01-01	1.38365995883942
2013-01-01	1.34669005870819
2014-01-01	1.35501003265381
2015-01-01	1.34406995773315
2016-01-01	1.35125005245209