Year	% of revenue
2014	2.39513444851133
2015	2.9408851224375825
2016	3.56258397156939
2017	2.8488976683001397
2018	3.449290463137828
2019	3.0949753275219356
2020	3.6506184542926055
2021	2.399651597520159
2022	2.3938192533364226