Year	% of revenue
2000	13.403037383653526
2001	13.575469422515377
2002	15.188693668881829
2003	15.423362963835089
2004	8.866714413389833
2005	6.925479095432513
2006	7.251654856605027
2007	7.524044142579639
2008	9.553878171343541
2009	9.127471810197203
2010	13.240180852764317
2011	10.215715248038054
2012	11.185740283631144
2013	7.75879548513862
2014	10.964774210785912
2015	9.920216175701931
2016	6.858311073395115
2017	12.185234132228453