Year	% of expense
2009	7.149603634794421
2010	5.595502235219372
2011	5.47819261264946
2012	5.480258295264479
2013	5.540196120782755
2014	5.740103578015001
2015	5.7530716466831455
2016	4.957001963665712
2017	4.728801374015569
2018	4.925122133008063
2019	4.559523999179753
2020	5.912123072480737
2021	5.842995074285614