Year	% of expense
2012	5.372718229223569
2014	5.143951817138097
2015	5.480280699237827
2016	6.072297240627359
2017	7.073307545607317
2018	9.512816947518937
2019	7.991067297226068
2020	8.306633092357213
2021	9.79886060915679