Year	% of expense
1996	21.034174391457736
1997	21.69816921293966
1998	21.746217416759848
1999	11.63685841327625
2000	9.646529240476154
2001	10.295820800211063
2002	14.634600427138574
2003	14.333969343834818
2004	14.726820868601864
2005	10.68193926478423
2006	11.978038973090008
2007	9.46726647713691
2008	17.928424439804086
2009	22.408096579338803
2010	21.69892411625931
2011	36.069791280077354
2012	34.45115931577105
2013	33.53997013119386
2014	32.83618820420948
2015	30.749931056483376
2016	31.7359658302081
2017	32.31511107314237
2018	30.974723411148002
2019	31.275796908544578
2020	44.4584410164762
2021	37.556557981711656
2022	42.02197469011452