Year maximum value in 2004 = 100 2006 59.9000621229 2007 59.2992468943 2008 58.3464240438 2009 55.093611272 2010 61.437545626 2011 63.3185685372 2012 62.8792751917 2013 62.2282907448 2014 62.0073241303 2015 62.3856976286 2016 64.2838372899 2017 67.1659312372 2018 66.1142975773 2019 69.3683980829 2020 75.9605517621 2021 76.3400650779