Year	% of expense
2004	3.99039661713664
2005	4.45001376644908
2006	4.26956946042112
2007	4.76305553003775
2008	4.29014719088449
2009	3.80475439438881
2010	5.0310859842025
2011	6.22922496291254
2012	6.95856982399306
2013	6.92223000436932
2014	8.33527550075351
2015	8.19308400454128