Year	maximum value in 2004 = 100
2006	16.5752636004
2007	16.8183937541
2008	15.7504270388
2009	20.5075749502
2010	21.7527972108
2011	19.9905824836
2012	20.2036709493
2013	20.73515875
2014	20.1483335869
2015	19.7155435817
2016	13.4869710214
2017	15.6395349069
2018	15.3423604905
2019	15.8508627094
2020	15.5093882313
2021	15.093762738