Year	% of revenue
1990	1.8948352898881748
1991	2.085661080074488
1992	3.054989816700611
1993	2.822618889542273
1994	4.177729366646243
1995	4.474103143163896
1996	3.7860239909179194
2006	8.828866886560023
2007	10.712853868636673
2008	15.213602665333692
2009	13.9234612877889
2010	15.38800990746458
2011	13.306402549044591
2012	13.310207646776314
2013	10.567836514667837
2014	10.73206450294692
2015	13.139758924479825
2016	12.118883268103776
2017	14.52496478655532
2018	14.658598568504058
2019	15.789297113263908
2020	16.691883236976647
2021	16.91867983919487
2022	13.803373617074588