Year	% of revenue
1996	6.142623037479516
1997	5.052264808362369
1998	3.695764909248055
1999	4.239972402546492
2000	3.112902491232864
2001	2.665002896742279
2002	2.475807021261567
2003	2.8711636481943392
2004	3.010126231100014
2005	2.425211272131358
2006	2.752932599044383
2007	3.345877345514002
2008	1.3386786288257422
2009	0.8774031550094881
2010	0.8744605600441286
2011	0.9621220301370578
2012	2.6511853592899888
2013	2.4878016964260756
2014	6.821647430452188
2015	9.913436936892092
2016	11.057077890823388
2017	11.197303626888562
2018	12.785137294189063
2019	11.710784389034838
2020	11.148719097638107
2021	10.745710499379285
2022	12.535025897936656