Year maximum value in 2004 = 100 2006 8.0805034833 2007 6.7826060028 2008 7.4501982796 2009 7.7445773526 2010 9.5597267774 2011 7.0051469098 2012 8.2186723425 2013 8.9402497522 2014 9.1981552985 2015 9.0477395429 2016 9.0715274736 2017 9.0157510575 2018 8.4808088371 2019 8.9134461255 2020 8.7807802901 2021 8.9035387976