Year	% of revenue
2004	33.70371909298784
2008	39.833764279402615
2009	42.60033861597437
2010	43.09863077461979
2011	29.331278655436776
2012	46.91411744923795
2014	78.54839547173833
2015	40.8205912732041
2016	56.14400977354768
2017	48.78222121956009
2018	48.69052224503571
2019	54.764873605322705
2020	59.68725359151915
2021	42.71214358006302