Year Z-score 1996-01-01 25.3175 1997-01-01 25.9841 1998-01-01 28.9183 1999-01-01 28.7038 2000-01-01 24.7290 2001-01-01 25.2739 2002-01-01 25.4963 2003-01-01 27.2739 2004-01-01 32.8577 2005-01-01 37.9483 2006-01-01 28.2144 2007-01-01 28.4524 2008-01-01 26.4198 2009-01-01 26.8063 2010-01-01 26.7543 2011-01-01 29.5239 2012-01-01 27.4283 2013-01-01 25.3544 2014-01-01 24.4939 2015-01-01 23.4965 2016-01-01 20.9541