Year	% of revenue
1996	17.50945371021176
1997	12.930770918871673
1998	19.900956996060156
1999	29.529704737238532
2000	16.049430434665798
2001	17.84539988308084
2002	13.3915688736761
2003	12.624443138291582
2004	9.795966108007187
2005	13.691900743166647
2006	13.015065006535048
2007	11.72358007368089
2008	8.540547978027732
2009	10.564316872023523
2010	5.680399581060369
2011	5.83624753995088
2012	5.326751681496761
2013	4.778207240479651
2014	5.718407897108322
2015	8.030502440200943
2016	7.957821237981341
2017	8.73831475977511
2018	5.92043989208687
2019	9.146514313829144
2020	20.524770011133704
2021	20.484270705904486
2022	17.545934869938595