Year	% of revenue
1990	9.870580638217726
1991	11.533032017746777
1992	11.660818713450292
1993	12.830677889673831
1994	12.914324358595039
1995	11.819765960231148
1996	13.476075436408976
1997	12.51946452227671
1998	11.214558230175939
1999	13.928529133112269
2000	12.68872262453267
2001	14.450391966256273
2002	14.08961864882883
2003	13.861640442480367
2004	12.926851368705222
2005	12.741719155871717
2006	15.878063793185081
2007	18.011004783080732
2008	18.433285116412545
2009	19.23436324193802
2010	16.25802581625358
2011	16.56028895156103
2012	16.179994375175777
2013	17.832586208391497
2014	16.69013256560091
2015	17.975383523579122
2016	15.288462708192412
2017	14.92537825467033
2018	16.064986286406548
2019	22.524627068125366
2020	17.35408225976984
2021	19.540395685942105
2022	26.523994715264763