Year	% of expense
2012	22.974346604375363
2013	16.828343768046018
2014	19.32875412850491
2015	16.507458004613916
2016	17.728991238631995
2017	12.328638949052332
2018	10.879125857408004
2019	11.648078765066293
2020	13.928850195128673
2021	15.324824305028603