Year	% of expense
1990	1.1510695187165776
1991	1.9881408096072635
1992	2.715520859565181
1993	2.859858046506103
1994	3.5614612404715293
1995	5.930726678809354
1996	5.8739774181954045
1997	5.658824228406328
1998	6.441873681797494
1999	7.33656603839011
2000	5.179914616792031
2001	5.256119757809889
2002	2.030385932962531
2003	3.2401616276456426
2004	3.920232287924806
2005	3.487781178768725
2006	4.263749567055256
2007	4.567203827873706
2008	4.934357481517776
2009	3.8459427567849405
2010	7.387694073815005
2011	7.211505838396402
2012	7.335738376666489
2013	10.008351699674852
2014	7.089512343757175
2015	9.991770582199052
2016	9.098939229480255
2017	9.809084144524968
2018	11.047184436340496
2019	11.0410081869052
2020	9.315566355543368
2021	9.55677514661133
2022	13.890986867983791