Year	% of expense
2012	7.739605500718659
2013	6.601712697520867
2014	5.848843508115934
2015	6.633902449309234
2016	5.341366000040907
2017	4.540853583529071
2018	4.21474381073746
2019	4.098819849909171
2020	5.971595794670653
2021	6.129992657058441