Year Number 1996 -0.940338909626007 1998 -0.683586835861206 2000 -0.519492506980896 2002 -0.821777701377869 2003 -0.680515766143799 2004 -0.673581480979919 2005 -0.865804314613342 2006 -0.994356155395508 2007 -1.02745187282562 2008 -0.97846394777298 2009 -1.05367839336395 2010 -1.02666425704956 2011 -0.967787086963654 2012 -0.918653786182404 2013 -0.996962249279022 2014 -1.05270552635193 2015 -0.940731823444366 2016 -0.694988965988159 2017 -0.701115071773529 2018 -0.712358295917511 2019 -0.77079850435257 2020 -0.886475205421448 2021 -0.966126441955566 2022 -1.01707208156586