Year	% of revenue
1990	35.246219464908876
1991	31.70437050508751
1992	44.37551713721593
1993	37.184154319412166
1994	43.09519168291098
1995	52.11302990103427
1996	54.66559131654779
1997	58.19973757321194
1998	56.93435996854254
1999	52.917416793611224
2000	53.980476681779685
2001	53.296996900716046
2002	54.264538802468145
2003	51.782804133751135
2004	50.510792686010596
2005	50.63392805920487
2006	49.47418061777882
2007	49.5046925289409
2008	50.00988218380685
2009	49.430012504176645
2010	52.26690662216401
2011	50.25988115122605
2012	50.36875108983725
2013	51.36886497008176
2014	50.4236358766845
2015	49.481022098618055
2016	47.965557891148734
2017	48.06967537646411
2018	45.18382277210945
2019	45.94328502238428
2020	47.13335112298161
2021	47.12897484371513
2022	46.07122218063135