Year	% of expense
2002	40.26450501587795
2003	37.32660203213158
2004	37.54859405677226
2005	38.214651748923515
2006	37.77231498095246
2007	37.78531128056971
2008	39.95355718411342
2009	41.6257820016138
2010	41.570288184918034
2011	41.156896563263146
2012	42.14436502893261
2013	41.95429256919365
2014	41.34953167499274
2015	40.535997959174395
2016	40.938725795327215
2017	40.21531590212139
2018	41.39951064013283
2019	40.57558147998567
2020	44.705174466406774
2021	44.688374796274196
2022	44.47748751468487