Year	% of revenue
2002	8.587624496715405
2003	8.749483755506608
2004	6.864719704598858
2005	6.104378665607868
2006	5.800703630357135
2007	4.668532027116898
2008	4.688122299181013
2009	4.9471650098320055
2010	4.976114649681529
2011	5.121234639363394
2012	5.064868668130872
2013	5.3451548266205675
2014	5.186237266147729
2015	5.361237406535358
2016	6.262298850066855
2017	6.210339638332352
2018	6.27948957877232
2019	5.977994003299279
2020	6.2532131060596265
2021	5.940175833683219
2022	4.933116616864862