Year	% of expense
1995	21.277766909129003
1996	20.771964902716917
1997	20.731179923985053
1998	22.932791101157886
1999	22.0500520132745
2000	20.460086125029573
2001	20.77296807663803
2002	22.199837982979858
2003	21.445305825871607
2004	22.56186004108273
2005	26.3096649287086
2006	23.31509664885676
2007	24.165834144908573
2008	21.25040508221645
2009	24.52357985866624
2010	21.024929551136523
2011	23.552351524001903
2012	22.686326644180816
2013	21.21513806941374
2014	21.440682137507018
2015	21.746500058435693
2016	21.3656038311662
2017	21.567139875243022
2018	22.30891601537455
2019	22.690811657279163
2020	20.10023074160305
2021	17.650295706145883
2022	19.243663056589387