Year	% of revenue
1993	4.609076807553699
1994	3.5320492935901413
1995	2.8366902149406283
1996	3.2037975535389824
1997	3.0440283482064014
1998	3.1322905919828905
1999	2.580677227188492
2000	2.224026460547574
2001	2.7985381632237036
2002	3.7134853375665418
2003	2.9334678535863845
2004	3.144266947986787
2005	3.222741972741973
2006	3.0741205007278647
2007	3.088914665844523
2008	3.0190240520741383
2009	3.8053059750631917
2010	4.045863146129671
2011	4.004824285776013
2012	4.19792999708134
2013	3.9382762902399753
2014	3.892735687622293
2015	3.1583400414021563
2016	2.739857360893412
2017	2.2241289195974585
2018	2.1860992856708683
2019	2.0796985356222057
2020	2.2668235050386016
2021	2.312476830334591
2022	3.3943167555337763