Year	% of revenue
1994	32.405905948621616
1995	30.54615741023021
1996	31.192308385677208
1997	30.42573302898553
1998	30.047020183434576
1999	31.82087562406877
2000	31.37868013269699
2001	31.856336173122298
2002	32.52786878745561
2003	31.877891216330895
2004	31.240656204023775
2005	31.601760133057134
2006	31.421497833711577
2007	30.861109964961692
2008	31.21818485047777
2009	33.331854648086214
2010	32.84018345217902
2011	31.8452440707989
2012	31.27369522402757
2013	31.05794117647059
2014	29.96184132048365
2015	29.821698223082215
2016	29.573249339168868
2017	31.04831967898345
2018	30.250196491269122
2019	30.839804728315713
2020	32.382945194564485
2021	31.660755054457773
2022	30.619967336759835