Year	Z-score
2007-01-01	3.1745400000000004
2008-01-01	2.6255599999999997
2009-01-01	7.6945600000000010
2010-01-01	5.9998400000000000
2011-01-01	4.7177800000000000
2012-01-01	4.4223000000000000
2013-01-01	6.2629500000000000
2014-01-01	6.2629500000000000
2015-01-01	6.3014100000000000