Year maximum value in 2004 = 100 2006 4.3556714589 2007 4.3556714589 2008 4.5560583135 2009 4.5519501483 2010 4.6520478402 2011 4.5572234333 2012 4.5572658013 2013 4.5552321376 2014 4.4040692931 2015 4.4050755329 2016 4.4050755329 2017 4.5143039346 2018 4.6562253784 2019 4.5735457916 2020 6.0414674084 2021 6.0372094252