Year	% of revenue
1990	51.732857246957664
1991	49.108508803649414
1992	48.28145287702751
1993	47.915934348214044
1994	47.98654841581221
1995	48.82156129239355
1996	51.08830389087
1997	51.82581797818725
1998	52.55682109428662
1999	53.73077015383877
2000	54.440714868910455
2001	52.888103793794485
2002	50.256064806418465
2003	50.348114846650304
2004	52.514282978519674
2005	53.11424703738156
2006	54.45306798859727
2007	54.833162729259776
2008	55.16834103097147
2009	53.50267418121172
2010	52.77041582811304
2011	53.8083962392606
2012	53.04289797974289
2013	53.139472333689895
2014	54.07004133934775
2015	54.011139558909406
2016	54.363074616417094
2017	54.45903709223381
2018	55.21803721958302
2019	54.51690035229701
2020	56.46238923438429
2021	54.59352101732452
2022	55.0903977187336