Year	% of expense
1995	3.7637521713954833
1996	8.542191902713926
1997	9.305631492618916
1998	14.907482834865588
1999	15.567746610081773
2000	18.63476733977173
2001	10.72961373390558
2002	12.766512923157253
2003	13.494033795146954
2004	7.337936720601876
2005	4.7511670227074925
2006	3.11087723642667
2007	2.1933972886546864
2008	2.1175384724613497
2009	2.96875
2010	3.6162813744391795
2011	4.681006076863213
2012	3.6668931092536257
2013	3.2503313105949645
2014	2.942448636309023
2015	3.41435366682348
2016	3.794304250345847
2017	4.291837763849866
2018	4.801330657151353
2019	5.010317787866281
2020	5.309036023623411
2021	4.847575001816025
2022	4.198979563755249