Year Number 1996 0.518067419528961 1998 0.521346211433411 2000 0.182292386889458 2002 -0.880716562271118 2003 -0.691475629806519 2004 -0.698035299777985 2005 -0.525074362754822 2006 -0.61456698179245 2007 -0.635693550109863 2008 -0.702629446983337 2009 -0.830836772918701 2010 -0.742940902709961 2011 -0.701964378356934 2012 -0.897686779499054 2013 -0.928134799003601 2014 -1.0661495923996 2015 -0.898022353649139 2016 -0.347571164369583 2017 -0.196299895644188 2018 -0.195977628231049 2019 -0.453079700469971 2020 -0.498344272375107 2021 -0.631172716617584 2022 -0.697565734386444