Year	% of expense
2004	8.561285029312533
2008	10.855692128430896
2009	7.022987138513153
2010	5.491915638591464
2011	4.5142814126116715
2012	5.647557139452183
2014	2.8036533909193126
2015	5.034801317293965
2016	1.1844440256101767
2017	2.1118666794368357
2018	2.2430434727949815
2019	5.010861246608276
2020	2.0452316649578566
2021	5.173792013339782