Year	% of revenue
1994	9.913705007380493
1995	11.05202464041708
1996	11.009437223466895
1997	12.664669826037493
1998	11.839751997138428
1999	11.425777385166633
2000	11.3426428690064
2001	10.713813115057624
2002	10.618502409051064
2003	11.090004078896962
2004	10.660347688882586
2005	7.3160352788156615
2006	6.942908856137892
2007	5.713089355420402
2008	5.028733927727096
2009	6.971904271487837
2010	6.275962573035697
2011	6.232162268893591
2012	5.966279974920638
2013	6.4609950158571
2014	7.124671412265506
2015	7.946630273688372
2016	8.797272798895861
2017	8.070563806876196
2018	9.119468161650582
2019	8.182512685895484
2020	9.006617612148947
2021	7.8366139597987745
2022	7.961117304984831