Year	Z-score
1996-01-01	13.1261
1997-01-01	14.3883
1998-01-01	15.3887
1999-01-01	15.9202
2000-01-01	14.9591
2001-01-01	13.6231
2002-01-01	12.8456
2003-01-01	13.8515
2004-01-01	14.3109
2005-01-01	14.1494
2006-01-01	14.0132
2007-01-01	14.4239
2008-01-01	15.6413
2009-01-01	16.9223
2010-01-01	16.9488
2011-01-01	17.4347
2012-01-01	19.8152
2013-01-01	20.6524
2014-01-01	21.3365
2015-01-01	21.2340
2016-01-01	19.7015