Year	% of expense
2002	19.205914991144198
2003	23.20097560095182
2008	26.208767017993654
2009	19.6151498446671
2010	24.40902714289974
2011	22.13443728089258
2012	25.186819030272684
2013	23.50164424703624
2014	22.55009143526589
2015	22.923639487221593
2016	21.921336705187446
2017	21.254824377607925
2018	20.698773301330867
2019	19.06589589164235
2020	15.805505613152542
2021	16.859774110658588
2022	22.30168462826669