Year	% of expense
2005	58.07051791281197
2006	51.75526012315325
2007	64.47721179624666
2008	66.95271225408649
2009	51.53185888884434
2010	56.56221669476107
2011	61.99053675923556
2012	61.475926326966544
2013	61.08787971685733
2014	60.35315769082944
2015	55.246633136141256
2016	56.692357612189724
2017	53.83973522070521
2018	48.81498958542208
2019	50.17520771676446
2020	50.22548724350732
2021	55.47287520691411