Year maximum value in 2004 = 100 2006 16.6731276695 2007 17.0525658031 2008 15.9720925135 2009 12.7593268389 2010 12.4214156216 2011 11.2951354335 2012 16.6679652622 2013 17.5617983418 2014 20.4970101534 2015 15.8073075719 2016 9.0449049735 2017 8.7562393536 2018 5.9359060624 2019 7.8492034714 2020 7.7538472178 2021 6.562284732