Year	% of revenue
1992	25.954932856788364
1993	24.864345829026973
1996	26.42705642522022
1997	27.96875105053546
1998	25.682517305358225
1999	27.81599706677673
2001	26.090212831332348
2002	27.593478267396947
2003	28.969713189325287
2004	27.203398022547418
2005	28.41764820319267
2006	27.15590935460302
2007	24.867675577446967
2008	25.986120661857832
2009	28.732013758462237
2010	28.10692006066588
2011	27.495593521896293
2012	26.53511229801285
2013	27.32678204281924
2014	25.295078038012292
2015	25.770109270528224
2016	28.969781707081694
2017	28.656551311012883
2018	27.27645071114685
2019	27.431174266972757
2020	27.602039355626772
2021	29.9147877432152
2022	24.511716542240762