Year	% of revenue
1998	17.6280965899324
1999	16.07935593014688
2000	11.86047733805391
2003	0.8103273673605464
2008	5.517972573329218
2009	5.84645978376934
2010	5.713400030776516
2011	15.33789657649281
2012	5.227829275338986
2013	7.5055928160376055
2014	6.112791004427728
2015	6.369668890965509
2016	3.652979984465679
2017	3.6568190262166733
2018	1.9401051704612493
2019	2.186697851897085
2020	2.1503605003736235
2021	1.8204896386501401
2022	1.4916376414470756