Year	% of revenue
1995	29.72387971405196
1996	29.112379047511883
1997	27.22372520751491
1998	28.560644848733702
1999	27.520830621602933
2000	28.95723513531805
2001	29.885411015977585
2002	31.47713985525838
2003	32.99330572598704
2004	35.67195608591824
2005	34.70884417350183
2006	32.153276010023504
2007	32.64998641575189
2008	30.984313675590247
2009	28.952004655018516
2010	29.784031518969133
2011	30.460859457623336
2012	29.18878444959222
2013	28.779987472692504
2014	28.802862834823166
2015	27.544797254819862
2016	29.281110392333165
2017	31.836929413130033
2018	31.469136034839813
2019	31.650098235996797
2020	31.328565803142403
2021	30.585699729674946
2022	31.367890241533726