Year	% of expense
1995	15.818473781549216
1996	14.153142455029247
1997	14.4834412585195
1998	13.1588023464491
1999	13.03373304942284
2000	11.955647086100845
2001	14.532645511042665
2002	13.830092559374327
2003	12.893752947011382
2004	12.006813855478232
2005	14.370160509911411
2006	13.189213250322268
2007	11.854101391956444
2008	11.91188308544492
2009	11.004088801075712
2010	10.539530585129368
2011	10.432376922311452
2012	10.806827444813134
2013	10.424570673097943
2014	10.686905098050262
2015	10.671558127941399
2016	10.273917688603367
2017	10.562463936408301
2018	10.889938564116566
2019	10.754975922413736
2020	10.739684975048247
2021	9.63656478541077
2022	10.642669046845398