Year Number 1996 0.935005784034729 1998 0.879612982273102 2000 1.08280909061432 2002 0.285476922988892 2003 0.0804403498768806 2004 -0.233039826154709 2005 -0.0605432577431202 2006 0.49083548784256 2007 0.374478042125702 2008 0.582659542560577 2009 0.447313606739044 2010 0.438403934240341 2011 0.591247260570526 2012 0.632442116737366 2013 0.643072605133057 2014 0.582419633865356 2015 0.662890195846558 2016 0.385635316371918 2017 0.26220178604126 2018 0.386042565107346 2019 0.117876663804054 2020 -0.0269290637224913 2021 -0.0148778762668371 2022 -0.0360050275921822