Year Number 1996 -0.687850117683411 1998 -0.554986298084259 2000 -0.556626617908478 2002 -0.48723691701889 2003 -0.499147057533264 2004 -0.610386073589325 2005 -0.438366830348969 2006 -0.451205492019653 2007 -0.424296855926514 2008 -0.53019917011261 2009 -0.627837359905243 2010 -0.620883345603943 2011 -0.660571336746216 2012 -0.70156067609787 2013 -0.712197959423065 2014 -0.656892597675323 2015 -0.652822732925415 2016 -0.606329381465912 2017 -0.682943880558014 2018 -0.779425084590912 2019 -0.85467791557312 2020 -0.738110244274139 2021 -0.646397411823273 2022 -0.42673471570015