Year	% of expense
2010	55.86623965493196
2011	53.53193960670828
2012	56.08151289511317
2013	57.4152534219441
2014	57.23640641263733
2015	61.778478872001095
2016	61.58867942419468
2017	64.08174012549755
2018	72.613458705095
2019	80.98766324538794
2020	76.92464687658392
2021	77.19321254085341