Year	% of expense
1990	5.292511609455581
1991	5.554018094731241
1992	1.1759909463458524
1993	1.3560891260985888
1994	0.9862651001158365
1995	0.7936659718105147
1996	0.5665424194766758
1997	0.49664494095577094
1998	0.5245538345474692
1999	0.6406028663680629
2000	0.801571580940772
2001	7.652743068159437
2002	7.4720224896163066
2003	7.6361229914962285
2004	7.609145665157242
2005	8.015407642297937
2006	7.390655903613307
2007	7.610569430867809
2008	11.924657574947261
2009	9.988557340169764
2010	7.755486287730095
2011	7.55430413186988
2012	7.305615139394278
2013	6.953962558491838
2014	6.8506988624169995
2015	6.592856235787246
2016	6.399861115282429
2017	6.6206819744369785
2018	6.278470171693407
2019	6.312148098829047
2020	8.622978166551402
2021	13.322286996676148
2022	5.842579095762587