Year maximum value in 2004 = 100 2006 9.0053629109 2007 8.536042726 2008 11.0391854945 2009 13.723934734 2010 13.7328050316 2011 14.5325655077 2012 15.3299175835 2013 14.9853670844 2014 19.2028831304 2015 17.068693564 2016 17.2752862633 2017 16.1343177118 2018 14.1867017714 2019 15.6923700807 2020 14.5947789863 2021 22.1821681964