Year	% of revenue
1992	11.883589329021827
1993	5.34445729390385
1994	9.616992290305602
1995	14.603212178600044
1996	16.6284339056174
1997	18.31025849847676
1998	21.711402106529572
1999	18.90175569667538
2000	17.790193000277032
2001	16.887914340099776
2002	17.33983477592872
2003	15.752482567724318
2006	7.342288823784812
2007	8.650017760437077
2008	13.681874426826871
2009	16.608794118071284
2010	13.143060202058743
2011	14.219570763812909
2012	17.31957574992927
2013	18.829905137059313
2014	19.775110793330906
2015	21.888905669257444
2016	24.36005371065015
2017	21.408178288545027
2018	18.78919120845999
2019	17.71571157831136
2020	16.6134297551342
2021	18.975064226950742