Year	% of expense
1998	7.639419903404375
1999	9.946861507804716
2009	6.041120713025364
2010	6.906684435541613
2012	9.610575477407592
2013	4.1776308515578355
2014	7.485098282853746
2015	6.538605977299825
2016	4.77144464989147