Year	% of expense
2003	34.0893107171579
2004	36.352784384889695
2005	35.165254019254675
2006	35.74007045309466
2007	37.06716949105291
2008	37.21246718366234
2009	36.01891699857008
2010	39.216900919724914
2011	34.00584094248524
2012	37.19993129162337
2013	33.7068844259777
2014	35.175965997151124
2015	36.15280091539232
2016	35.934104935225
2017	35.25509612057523
2018	33.71109108466725
2019	33.995170679145566
2020	36.95807543916109
2021	36.77375038660633