Year	% of expense
2001	3.506499582618203
2002	4.303552309352466
2003	5.6713499848801865
2004	6.384107133226751
2005	6.17007696569857
2006	6.209247184350919
2007	6.706816315357241
2008	7.754394257771661
2009	13.267120731831424
2010	13.355104264294429
2011	25.166411168937536
2012	13.631111751039422
2013	13.185321379114109
2014	13.36311437729136
2015	12.90368037536643
2016	12.838044795125347
2017	13.047160409723455
2018	12.950753050101962
2019	12.336120614322517
2020	11.338700182238577
2021	12.684364128697803
2022	11.478510656584618