Year Number 1996 -0.725473284721375 1998 -0.79578822851181 2000 -0.906720697879791 2002 -0.853914260864258 2003 -0.760160028934479 2004 -0.793166995048523 2005 -1.1232408285141 2006 -1.31729280948639 2007 -1.32194709777832 2008 -1.38291394710541 2009 -1.32975375652313 2010 -1.26945745944977 2011 -1.19611263275146 2012 -1.1348477602005 2013 -1.11489605903625 2014 -0.935829699039459 2015 -1.01296901702881 2016 -1.04268062114716 2017 -0.947567045688629 2018 -0.928147077560425 2019 -0.913639008998871 2020 -0.959660351276398 2021 -1.09884703159332 2022 -1.14780843257904