Year	% of revenue
2002	12.71489176438519
2003	10.300251839500742
2004	13.541266638544403
2005	12.572881006407735
2006	13.67875521554284
2007	12.875770932154076
2008	12.972121774008588
2009	11.630171901455435
2010	10.992687758728225
2011	10.692071918952726
2012	11.643644569109386
2013	11.69689864944542
2014	10.879851983493234
2015	11.184154409969718
2016	11.279688053881602
2017	12.624479343838965
2018	11.588071960971998
2019	10.217721956045022
2020	9.389898801398372
2021	10.630028894435261
2022	11.144133346718377