Year	% of expense
1992	40.893470790378004
1993	54.187604690117254
1994	61.02977061981454
1995	39.31929625458183
1996	24.161972307669167
1997	22.616111693208296
1998	19.485106949137446
1999	15.041029995031849
2000	14.329104954807045
2001	14.478331910319808
2002	12.462890531136297
2003	16.854409880032
2004	18.93374204803022
2005	11.773415567536613
2006	15.396164996824774
2007	13.88787333363106
2008	11.851666260919739
2009	11.514663918599725
2010	9.854333069854352
2011	10.227172449249728
2012	11.51218061018742
2013	11.55476752101572
2014	12.520479787614166
2015	11.138030945996926
2016	10.414648870479356
2017	13.360593484865937
2018	14.285578760603123
2019	13.576145536031156
2020	12.786983519734205
2021	12.686222894108795
2022	13.251325569500723