Year	Z-score
1998-01-01	3.9013500000000000
1999-01-01	6.1316800000000000
2000-01-01	4.8329500000000000
2001-01-01	3.5938199999999996
2002-01-01	3.5843700000000000
2003-01-01	3.8597400000000000
2004-01-01	4.1487200000000000
2005-01-01	5.1706300000000000
2006-01-01	4.4973900000000000
2007-01-01	4.8911300000000000
2008-01-01	5.5858600000000000
2009-01-01	6.7849000000000000
2010-01-01	7.7407000000000000
2011-01-01	6.0015500000000000
2012-01-01	6.9335600000000010
2013-01-01	10.0677000000000000
2014-01-01	8.3262800000000000
2015-01-01	9.9549899999999990