Year	% of revenue
2004	31.321180818473916
2005	32.260689777647045
2006	30.17086260178904
2007	41.05081187389402
2008	43.44918957578959
2009	40.57230701437097
2010	42.50342505408428
2011	39.51428507820544
2012	42.15187513047779
2013	41.70772251933829
2014	44.159074279699425
2015	39.48396096240464
2016	37.809307242196425
2017	38.46832617741355
2018	40.07776297101287
2019	47.88233983853948
2020	46.49982044640204
2021	52.48153994270862
2022	54.39843284147358