Year	% of expense
2003	10.888163845025224
2004	14.461140692602973
2005	13.383919259605989
2006	16.286036049746457
2007	15.556803102776334
2008	18.297277250928595
2009	18.95829427295444
2010	20.036691264600126
2011	21.408320724219124
2012	21.646653309595813
2013	21.98803109627189
2014	26.525372986272604
2015	26.30362470258018
2020	8.204957073078614