Year	maximum value in 2004 = 100
2006	17.0312079416
2007	16.2631013574
2008	19.9860895975
2009	19.3033930144
2010	19.9469291655
2011	19.959116331
2012	19.5016811904
2013	21.3572389453
2014	22.4579503436
2015	21.5692586524
2016	20.6383670749
2017	18.9750549279
2018	19.605379262
2019	19.9702011986
2020	19.9814975669
2021	19.2845020632