Year	% of expense
2010	20.441936506952338
2012	22.886879979358998
2014	21.529402505794025
2015	21.456717315623298
2016	20.66499107887083
2017	22.84029563455688
2018	17.93291835339172
2019	19.07478222127424
2020	16.955256600027568
2021	17.309885540616687