Year	% of expense
1994	14.90308150705564
1995	9.924177637721424
1996	11.531600272057316
1997	12.355880977421126
1998	11.864185244962806
2008	18.2742141751363
2009	18.95233922399104
2010	17.908275511930952
2011	18.348070948368125
2012	14.033643197668194
2013	14.16192330121808
2014	14.921756998167556
2015	14.418290665499514
2016	13.502543631185649
2017	12.195251433521635
2018	16.340460286439342
2019	15.811081584577597
2020	14.688456947000994
2021	14.254852534018312