Year Number 1996 -1.53094363212585 1998 -1.1040164232254 2000 -1.24837958812714 2002 -1.41743767261505 2003 -1.56096339225769 2004 -1.3047730922699 2005 -1.41722476482391 2006 -1.14034521579742 2007 -0.916478335857391 2008 -0.875740170478821 2009 -0.991805791854858 2010 -1.00055825710297 2011 -0.976101815700531 2012 -0.868966519832611 2013 -0.838690638542175 2014 -0.9411261677742 2015 -0.804575800895691 2016 -0.71827632188797 2017 -0.569948792457581 2018 -0.701724708080292 2019 -0.694264531135559 2020 -0.811034500598907 2021 -0.937743246555328 2022 -0.807034194469452