Year	maximum value in 2004 = 100
2006	28.3618810792
2007	29.4664678893
2008	30.9596422706
2009	32.5817470639
2010	33.8549394508
2011	35.0374445248
2012	34.0729676871
2013	39.3469192343
2014	38.4086542533
2015	35.2652857021
2016	39.632563945
2017	39.9638535497
2018	38.4084460113
2019	39.8671202607
2020	41.2569498275
2021	39.0636958837