Year	% of revenue
2013	2.5937562394717606
2014	2.9168109797344726
2015	3.803043164044734
2016	6.738277192411093
2017	6.448177019630344
2018	7.074127565749734
2019	8.385088663956877
2020	10.168949750999351
2021	3.940284032762621
2022	4.662799170163943