Year	% of expense
2010	5.339412720628653
2012	5.219946070592773
2014	4.778711841088324
2015	5.949761211361025
2016	7.418696414435145
2017	6.67622546823192
2018	10.582178375769388
2019	6.884049208741495
2020	7.36623170621621