Year	% gross
2007	11.0271396636963
2008	12.891300201416
2010	14.5729198455811
2011	6.11985349655151
2012	9.79728031158447
2013	11.4947204589844
2014	11.2993297576904
2015	12.1555204391479
2016	13.9851398468018
2017	14.6863899230957