Year	% of revenue
1985	0.4139501190106592
1986	0.20611165875078413
2005	0.34486441696781595
2006	0.3274779249702438
2007	0.3072730617855811
2008	0.3183844100294864
2009	0.3455907038500768
2010	0.08549806386396439
2011	0.0835845498234651
2012	0.07110063797076357
2013	0.07386376528264439
2014	0.06438934651601956
2015	0.609653331664736
2016	0.5279847162498382
2017	0.48562133309393823
2018	0.42087722699963076
2019	0.5021468701815937
2020	0.5242976633216087