Year	% of revenue
2009	13.387137660302475
2010	10.14943955431473
2011	8.577739904545059
2012	11.680135055299301
2013	10.416318062415861
2014	10.879851983493234
2015	10.966127010524833
2016	9.829758154271849
2017	10.210606818799908
2018	10.554266938410922
2019	10.176352466920713
2020	9.999972093575865
2021	10.31178881111671