Year	% of revenue
2002	33.71105089994194
2003	34.344404150641026
2004	37.0027592333264
2005	35.90354124205148
2006	35.5963174302557
2007	35.885159789485016
2008	34.22331137201864
2009	33.14482870297799
2010	32.79027007885812
2011	33.57289365539805
2012	34.26404107941145
2013	34.580028985876396
2014	33.51344095043125
2015	34.56535693773438
2016	35.528815438156684
2017	36.46496095303803
2018	36.18799958306307
2019	34.91717990726232
2020	36.006365792659444
2021	35.807728262835454