Year	Ratio
1971-01-01	0.922129988670349
1974-01-01	1.230219960212710
1975-01-01	0.949530005455017
1976-01-01	0.934520006179810
1977-01-01	1.025449991226200
1978-01-01	0.914640009403229
1979-01-01	0.977580010890961
1984-01-01	0.864870011806488
1992-01-01	0.926209986209869
2007-01-01	0.973349988460541
2008-01-01	0.957740008831024
2009-01-01	0.958750009536743
2010-01-01	0.915600001811981
2011-01-01	0.920660018920898
2012-01-01	0.935050010681152
2014-01-01	0.926649987697601
2015-01-01	0.943440020084381