Year	% of profit
2005	25.3
2006	25.1
2007	25.1
2008	25.1
2009	24.8
2010	24.5
2011	24.5
2012	27.7
2013	27.7
2014	28.9
2015	29.9
2016	31.4
2017	33
2018	34
2019	34