Year	% of expense
2012	6.310611151184172
2014	6.2952431566720115
2015	5.704387493027023
2016	4.077351475398604
2017	4.327078804533065
2018	6.121058489692498
2019	4.211470446056553
2020	6.138792637871185
2021	4.552089633642274