Year	% of revenue
1996	35.09494953104829
1997	39.39270463213482
1998	37.958576942968804
1999	39.16282958382
2003	38.02919260752111
2004	38.04559210955084
2005	37.71658959251164
2006	37.73765335568562
2007	38.176513903551054
2008	36.729821221823805
2009	35.42600850951984
2010	36.80279125005829
2011	36.15125063701367
2012	35.37481712538252
2013	35.86528215723531
2014	33.93890196728378
2015	36.54143993669936
2016	35.065954575006124
2017	35.522436939942054
2018	34.15426418088194
2019	32.721585138293634
2020	35.931457933281195
2021	34.065220058397145
2022	30.559665806126006