Year	Ratio
1971-01-01	0.983579993247986
1972-01-01	0.988380014896393
1973-01-01	0.994859993457794
1974-01-01	0.997550010681152
1976-01-01	0.996420025825500
1977-01-01	0.994470000267029
1978-01-01	1.002500057220460
1979-01-01	0.991339981555939
1980-01-01	0.994579970836639
1981-01-01	0.994340002536774
1982-01-01	0.996420025825500
1984-01-01	1.007390022277830
1985-01-01	1.022330045700070
1986-01-01	0.997609972953796
1987-01-01	0.991240024566650
1988-01-01	0.980340003967285
1989-01-01	0.974699974060059
1991-01-01	0.974089980125427
1992-01-01	0.973699986934662
1993-01-01	0.981469988822937
1995-01-01	0.974470019340515
1996-01-01	0.972679972648621
1997-01-01	0.973940014839172
1999-01-01	0.972060024738312
2000-01-01	0.966409981250763
2001-01-01	0.985790014266968
2003-01-01	1.001109957695010
2005-01-01	1.003180027008060
2006-01-01	1.000210046768190
2007-01-01	0.990549981594086
2008-01-01	0.995949983596802
2009-01-01	0.993629992008209
2010-01-01	1.000030040740970
2011-01-01	1.007099986076350
2012-01-01	1.021479964256290