Year	% of revenue
1995	31.966890027591642
1996	20.9636517328825
1997	16.53898152320865
1998	13.936395759717316
1999	8.285157819890562
2000	4.946996466431095
2001	10.334606546765041
2002	7.14419718234364
2003	8.551800379027164
2004	15.85686878151073
2005	13.227044582226158
2006	14.177661988402388
2007	11.580859584657942
2008	17.440011434901464
2009	15.155406625599454
2010	15.061127359261747
2011	9.026025964437334
2012	10.39356714569914
2013	16.055992269723955
2014	16.251257003304122
2015	20.369033375964353
2016	19.550890196378084
2017	19.902675579652797
2018	15.782030020120047
2019	15.09459288148485
2020	16.721024077832443
2021	15.568908803646819
2022	14.749893990405493