Year	% of revenue
1997	15.118972415245317
1998	15.563189673120966
1999	17.218182717514964
2011	6.98900466470528
2012	8.16658357488143
2013	8.263178348916748
2014	8.269640201492393
2015	0.9826088829319808
2016	0.6555045706070737
2017	1.3156123798433454
2018	1.263103205022284
2019	17.488816943506652
2020	9.430198451831
2021	10.518083690487805
2022	14.411615516691686