Year	Z-score
1999-01-01	20.125160220
2000-01-01	19.366832730
2001-01-01	18.523918150
2002-01-01	15.178485870
2003-01-01	11.999833110
2004-01-01	12.925530430
2005-01-01	13.136169430
2006-01-01	12.340928080
2007-01-01	10.453510280
2008-01-01	9.750309944
2009-01-01	10.222902300
2010-01-01	11.991103170
2011-01-01	13.362435340
2012-01-01	12.218072890
2013-01-01	11.214616780