Year	% of expense
1994	0.5262576822581239
1995	16.549353450410365
1996	13.16551656043268
1997	16.745044556480337
1998	20.17230747337713
1999	18.08146109253457
2000	18.390724851837756
2001	13.121694941798397
2002	13.400025731306531
2003	10.24256158856342
2004	11.873915119184465
2005	17.287913519042604
2006	21.469549697285217
2007	17.505668254428613
2008	17.849498229414486
2009	14.489296741813318
2010	17.81788969180978
2011	16.747433014494646
2012	16.1329064304947
2013	13.79529550479164
2014	15.046680114162204
2015	13.887366826964929
2016	13.666477288191395
2017	13.098616741443598
2018	14.130345620622084
2019	11.022999570385474
2020	12.90351848328775
2021	11.859159163328819
2022	12.79629022312545