Year	% of revenue
2004	14.082448556198981
2005	14.254323267532904
2006	14.826201722363756
2007	12.66655281074504
2008	12.631531082882166
2009	14.243279043101179
2010	12.923850307513748
2011	13.384044529808506
2012	13.079093354196267
2013	1.6198352884449614
2014	1.4094924262584523
2015	0.7262362309551587
