Year	% of expense
2001	6.401566043722311
2002	6.854243915475079
2003	8.012896123299521
2004	6.75923709201181
2005	7.067376152289589
2006	3.8661594596692805
2007	6.316434995911692
2008	3.707684040838259
2009	8.393656135476299
2010	10.602272541664172
2011	14.803456659364993
2012	15.083227768754945
2013	11.82098632984785
2014	9.982007611202281
2015	38.236947049805785
2016	35.263089018099315
2017	34.6572403259254
2018	38.55109447487693
2019	37.438104921568105
2020	37.996673282028034
2021	36.2442183864122
2022	42.72332593579044