Year	% of revenue
2012	2.7169226933602775
2013	2.7615754693942494
2014	2.4363618299661436
2015	2.9572775341752195
2016	2.7294018587781532
2017	2.413507867524436
2018	2.2964254908161568
2019	1.980948055841708
2020	1.6872393569459891
2021	0.7652419027137225