Year	% of expense
1991	1.1488955089652098
1992	1.1149249871978837
1993	0.9604892828877424
1995	3.9417593027097277
1996	4.254741817959839
1997	4.584592243449583
1998	4.87275150134418
1999	4.739705867120048
2000	5.1019785826978366
2001	5.064678000511768
2002	4.831446909707981
2003	4.729569630319523
2004	4.650453261796125
2005	4.723562149888237
2006	4.76366405491422
2007	4.825978780115393
2008	4.841198651288121
2009	4.586662561499424
2010	4.510664494987773
2011	4.698196997312514
2012	4.659384715725249
2013	4.664119425315216
2014	4.593102822118364
2015	4.579096086494798
2016	4.485895907204186
2017	4.508688464726253
2018	4.504816463722528
2019	4.510717895934015
2020	4.141731276018016
2021	4.193829842777527
2022	4.326252677299642