Year	% of revenue
1994	0.17781798775911814
1995	0.2460623514186992
1996	8.567960546111987
1997	6.848246338202962
1998	7.567807309139224
1999	7.208656837581046
2008	61.86503203897232
2009	58.85185541374146
2010	68.46146110915582
2011	67.95136383011948
2012	62.763581030570315
2013	60.1265903551421
2014	56.96999299199388
2015	44.68734714062256
2016	49.21328505620747
2017	54.01595356604355
2018	59.720539078681036
2019	59.624287503655594
2020	44.76722336635449
2021	53.914630735000124