Year	% of revenue
2004	42.413643705399316
2005	48.306400910094425
2006	45.28021289478482
2007	45.70754913056263
2008	43.02956295840003
2009	34.27234984067653
2010	35.86502350987565
2011	38.80567255688757
2012	42.4256091561468
2013	37.07218507003309
2014	44.654548536898844
2015	46.00925952280308
2016	43.31414455584515
2017	47.08457675502755
2018	39.87636149928888
2019	40.887995268026806
2020	45.31667584376565
2021	47.993521035388085
2022	46.0112559437667