Year	% of expense
1990	0.4533393078436452
1991	0.4030474318014254
1992	0.6107338092083676
1993	0.3916468645776836
1994	0.8397086298221503
1995	7.739673004696762
1996	8.130567550975778
1997	7.8101161686011125
1998	7.640722749070468
1999	8.030280506867395
2000	8.848816308591118
2001	7.170349893497055
2002	7.354280858947311
2003	7.330279531823826
2004	7.770731150183058
2005	7.844805054517051
2006	7.908431635407517
2007	7.757293314709757
2008	8.154166537158487
2009	8.40439138159532
2010	7.872569251396302
2011	8.025454469646432
2012	8.137051352514453
2013	7.923152340142028
2014	8.484249310707485
2015	8.659080575078107
2016	8.886040824764914
2017	9.125388941123589
2018	9.440233741100105
2019	9.791687994843748
2020	12.51042169188451
2021	10.438155250286796
2022	9.980221903214254