Year	% of revenue
2011	20.331294716545848
2012	18.527741721400076
2013	13.684082442993532
2014	15.532704715188888
2015	13.378731714985232
2016	14.178187755435282
2017	22.137282426629557
2018	14.780042551660808
2019	14.576587658061339
2020	12.644731374610666
2022	19.047669641764013