Year	% of expense
2010	25.569175927244693
2012	27.285678645990625
2014	23.12969938237075
2015	23.094816861814564
2016	22.519841238724165
2017	26.295586432247426
2018	24.404807518070793
2019	23.046214408851046
2020	18.9399399349465
2021	22.09267898316357
