Year Index 1992-01-01 29.7 1993-01-01 28.9 1995-01-01 39.3 1996-01-01 35.2 2002-01-01 29 2003-01-01 28.7 2004-01-01 28.9 2005-01-01 29 2006-01-01 29.8 2007-01-01 27 2008-01-01 26.6 2009-01-01 25.3 2010-01-01 24.8 2011-01-01 24.6 2012-01-01 24.7 2013-01-01 24.6 2014-01-01 24 2015-01-01 25.5 2016-01-01 25