Year	Ratio
1971-01-01	0.960099995136261
1976-01-01	1.071409940719600
1977-01-01	1.081159949302670
1978-01-01	1.030670046806340
1979-01-01	0.992730021476746
1980-01-01	0.799009978771210
1981-01-01	0.785650014877319
1982-01-01	0.799510002136230
1983-01-01	0.775049984455109
1984-01-01	0.765569984912872
1985-01-01	0.776080012321472
1986-01-01	0.785260021686554
1987-01-01	0.789969980716705
1988-01-01	0.797190010547638
1989-01-01	0.812009990215302
1990-01-01	0.815259993076324
1991-01-01	0.819980025291443
1992-01-01	0.807820022106171
1999-01-01	0.959010004997253
2000-01-01	0.892030000686646
2001-01-01	0.941739976406097
2002-01-01	0.960520029067993
2003-01-01	0.884829998016357
2004-01-01	0.905870020389557
2005-01-01	0.894150018692017
2006-01-01	0.906729996204376
2007-01-01	0.887799978256226
2008-01-01	0.885909974575043
2009-01-01	0.927699983119965
2010-01-01	0.990649998188019
2011-01-01	1.032559990882870
2012-01-01	1.070709943771360
2013-01-01	1.074349999427800
2014-01-01	1.095100045204160
2015-01-01	1.085340023040770
2016-01-01	1.098090052604680