Year	% of revenue
1995	58.3326012474743
2001	43.724978440496365
2002	47.055725138577586
2003	49.845249148870316
2004	49.56807310630399
2005	43.96218603367375
2006	47.16311581879293
2007	42.829705505761844
2008	37.97682483295272
2009	34.622925289567235
2010	42.37481899245484
2011	40.95607741665687
2012	39.18466320708884
2013	39.83462671391618
2014	41.16053069576348
2015	25.85287780338182
2016	26.862031238626916
2017	27.802781226264862
2018	24.60155503259376
2019	25.132978986810823
2020	22.800362998339928
2021	23.91822268869517
2022	23.03077924986539