Year	% of revenue
2009	29.41367332518737
2010	30.476864510554975
2011	34.1711526284463
2012	36.70962110571695
2013	25.265957069697905
2014	35.86115061345542
2015	33.20434707328632
2016	33.75907572367252
2017	33.806519166029354
2018	37.82391621394324
2019	38.58031231013962
2020	37.777253891209625
2021	37.17280372697541
2022	32.74370269417376