Year	% of expense
2009	5.326732429915425
2010	5.326732429915425
2011	4.4685326404810075
2012	5.067173911961976
2013	6.757306886580153
2014	7.355268557614621
2015	9.007846817222458
2016	10.022323173132094
2017	9.149938357277593
2018	10.582178375769388
2020	10.180135253680673
2021	9.901544572315869
2022	9.752581595035158