Year Number 1996 0.232784986495972 1998 -0.118997246026993 2000 0.0961097478866577 2002 -0.0474211908876896 2003 0.0996745452284813 2004 0.358144611120224 2005 -0.0028113410808146 2006 -0.124705359339714 2007 -0.391314208507538 2008 -0.20475609600544 2009 0.3261559009552 2010 0.456775397062302 2011 0.383940756320953 2012 0.274199098348618 2013 0.338074296712875 2014 -0.332812041044235 2015 -0.3187076151371 2016 -0.244855865836143 2017 -0.194125235080719 2018 -0.188686534762383 2019 -0.427999049425125 2020 -0.253533631563187 2021 -0.213269129395485 2022 -0.134738370776176