Year	% of expense
2002	25.013426393826162
2003	21.987796543480595
2004	23.00180043590931
2005	22.711530072091065
2006	21.310302362114523
2007	21.102469972080335
2008	21.010052996497055
2009	19.059303885964958
2010	17.126622713746862
2011	15.462604137816871
2012	14.550011705560504
2013	14.481081160283868
2014	11.546408117265015
2015	11.854686083661964
2016	11.441852149816752
2017	22.84029563455688
2018	21.38000655349515
2019	13.457711696412494
2020	9.953402019270813
2021	9.790114435196687
2022	10.345097850241466