Year	% of profit
2005	38.9
2006	38.8
2007	38.8
2008	39.1
2009	38.2
2010	38.2
2011	37.6
2012	37.4
2013	37.4
2014	37.3
2015	37.3
2016	35.6
2017	35.6
2018	36.8
2019	36.8