Year	% of expense
2002	27.77924910180199
2003	32.35881424141307
2008	34.267468852495
2009	35.48689961532996
2010	33.45259943374186
2011	30.637587305157314
2012	29.453081263337044
2013	28.919974393282537
2014	23.15490001507559
2015	23.881158647706286
2016	25.26978260507756
2017	24.904330705681694
2018	26.59784245655939
2019	24.466900348222154
2020	23.809110402008788
2021	20.70850568430842
2022	25.22808298838386
