Year maximum value in 2004 = 100 2006 28.1235691425 2007 29.8851900639 2008 33.3138140725 2009 31.9030946737 2010 40.385610712 2011 40.1604498772 2012 42.3606178118 2013 42.9087713896 2014 45.1201029227 2015 42.6593306154 2016 51.8923475117 2017 55.7289775396 2018 55.4614900067 2019 52.6211088499 2020 60.7216445811 2021 59.2965321439