Year	% of revenue
2013	12.582189413157568
2014	13.548466597268982
2015	16.093206702466702
2016	14.419068743951941
2017	13.678294058455865
2018	14.251332543901626
2019	13.432216531986452
2020	15.428389248130534
2021	11.99541503607441
2022	12.345227732380406