Year	Ratio
1971-01-01	0.747160017490387
1972-01-01	0.740999996662140
1973-01-01	0.779200017452240
1974-01-01	0.816470026969910
1975-01-01	0.836950004100800
1976-01-01	0.855610013008118
1977-01-01	0.884760022163391
1978-01-01	0.921720027923584
1979-01-01	0.921639978885651
1980-01-01	0.963800013065338
1981-01-01	0.933369994163513
1982-01-01	0.917859971523285
1983-01-01	0.904640018939972
1984-01-01	0.878920018672943
1985-01-01	0.905910015106201
1986-01-01	0.909940004348755
1987-01-01	0.924759984016418
1988-01-01	0.979690015316010
1989-01-01	0.984250009059906
1990-01-01	1.002470016479490
1996-01-01	1.043200016021730
1998-01-01	1.012560009956360
1999-01-01	0.984019994735718
2000-01-01	0.967379987239838
2001-01-01	0.974240005016327
2002-01-01	0.997850000858307
2003-01-01	0.989859998226166
2004-01-01	0.981360018253326
2005-01-01	0.977090001106262
2006-01-01	1.031149983406070
2007-01-01	1.030359983444210
2008-01-01	1.035240054130550
2009-01-01	1.042979955673220
2010-01-01	1.046350002288820
2011-01-01	1.046659946441650
2012-01-01	1.048179984092710
2013-01-01	1.028550028800960
2014-01-01	1.018399953842160
2015-01-01	1.043670058250430
2016-01-01	1.056929945945740