Year	% of revenue
1990	27.804983049023303
1991	26.184798984542745
1992	27.581073896863373
1993	27.173831354276267
1994	32.149287797455514
1995	26.327752102432
1996	31.7714827514547
1997	32.099611871615494
1998	30.136414788790383
1999	30.654409442602244
2000	32.90370582608173
2001	39.34556863268652
2002	43.638903662199716
2003	44.0249669265629
2004	37.42637800073114
2005	29.143089979068993
2006	29.745624279919824
2007	30.701966676414337
2008	30.951330044094448
2009	42.6806107232147
2010	42.267570503262114
2011	37.57128254363276
2012	38.29549076591356
2013	38.49849563430474
2014	36.76403902715808
2015	34.8902193450038
2016	36.08033233245632
2017	39.98591708281581
2018	44.09873288543926
2019	47.46936268815495
2020	71.38253035735612
2021	71.62010040776855
2022	77.76997688052553