Year Number 1996 -1.40605127811432 1998 -1.35108137130737 2000 -1.15839385986328 2002 -1.24116063117981 2003 -1.14207339286804 2004 -0.978848516941071 2005 -1.15841937065125 2006 -1.07245790958405 2007 -1.12784206867218 2008 -1.09022438526154 2009 -1.12183570861816 2010 -0.931619644165039 2011 -0.957298815250397 2012 -0.936370611190796 2013 -1.0658118724823 2014 -0.791394650936127 2015 -0.904887020587921 2016 -1.09165561199188 2017 -1.185950756073 2018 -1.16391563415527 2019 -1.11671459674835 2020 -0.759621620178223 2021 -0.646949529647827 2022 -0.756126046180725