Year Number 1996 -1.0479496717453 1998 -0.992841362953186 2000 -1.0572007894516 2002 -1.25275146961212 2003 -1.38021075725555 2004 -1.25965797901154 2005 -1.1734801530838 2006 -1.01482832431793 2007 -0.956503331661224 2008 -0.874180316925049 2009 -1.04979801177979 2010 -0.974354088306427 2011 -1.00235879421234 2012 -0.856835246086121 2013 -0.803554475307465 2014 -0.756003856658936 2015 -0.819004893302917 2016 -0.811310946941376 2017 -0.904718279838562 2018 -0.863172948360443 2019 -0.968699157238007 2020 -0.880950748920441 2021 -0.663793444633484 2022 -0.805023312568665