Year	% of revenue
2003	40.74288090704139
2004	44.35581583198708
2005	45.86188580656667
2006	44.451022893849405
2007	43.033061082790496
2008	41.95522083269076
2009	39.60817192369469
2010	44.68758153159537
2011	49.42740956636578
2012	47.16401033617624
2013	49.77619918618268
2014	44.36048766305354
2015	48.356526321247664
2016	45.87893031832037