Year	% of revenue
2007	1.8554819935412803
2008	1.4468514913505082
2009	1.9906760130747219
2010	2.8896598131414977
2011	3.5331036094085424
2012	5.115310147712137
2013	5.956251153134631
2014	7.105197868686873
2015	7.5295179648221575
2016	7.213640179525808
2017	6.147829162465921
2018	5.249958704693268
2019	4.799174571067601
2020	4.551925365378967
2021	4.712360985464101
2022	3.6307691528274266