Year	maximum value in 2004 = 100
2006	26.2165948181
2007	27.9033221826
2008	29.2907757234
2009	28.9702964267
2010	30.8698537772
2011	29.3097066829
2012	29.0216146654
2013	31.0187482866
2014	33.3886128847
2015	32.406980102
2016	34.2468472929
2017	32.5961142706
2018	34.1643048892
2019	35.6691751858
2020	37.242980096
2021	35.7426324651