Year	% of expense
1999	6.528071667309128
2000	1.3511021822853349
2001	6.533375429095016
2002	7.921871857331218
2003	7.276078565303487
2004	7.16973689928086
2005	17.611823878405605
2007	13.556651963113737
2008	15.425803524411224
2009	14.427243277018691