Year	% of expense
1994	62.85665206095389
1995	51.74349460063746
1996	52.08633706252015
1997	51.40568726049051
1998	50.01282317876205
1999	50.7593582791449
2000	52.268661368216414
2001	51.13493379425972
2002	51.456042667487516
2003	51.445701708241366
2004	49.91170227609656
2005	52.16597604372163
2006	52.06511323033297
2007	50.614951840626546
2008	50.153168986017064
2009	53.6158145318673
2010	52.317875897384255
2011	51.419373770143395
2012	51.95376526372254
2013	52.6382156906281
2014	52.34021101502567
2015	53.009001843404235
2016	53.17817033088278
2017	51.011999306099796
2018	54.10202095379859
2019	53.26956706625131
2020	54.70065254812629
2021	52.144425371452996
2022	51.53980704695892