Year	% of revenue
2004	11.930449859489041
2005	13.999678902939483
2006	14.496798984211207
2007	15.360239472772141
2008	13.014284837899993
2009	13.980970041283808
2010	14.60722808462701
2011	16.08625244053437
2012	11.292060665837015
2013	8.035374610565096
2014	12.148442582008508
2015	11.134608872500715
2016	9.577394433946768
2017	9.01802263224159
2018	8.022918549210878
2019	7.774911675145643
2020	12.689682491160765
2021	6.9052115808200405
2022	7.748415665174132