Year	Ratio
1990-01-01	0.172810003161430
1992-01-01	0.400499999523163
1999-01-01	0.758729994297028
2000-01-01	0.734679996967316
2003-01-01	0.776960015296936
2009-01-01	0.713930010795593
2010-01-01	0.744589984416962
2011-01-01	0.786249995231628
2012-01-01	0.864979982376099
2013-01-01	0.867299973964691
2014-01-01	0.812009990215302