Year	% of expense
2002	20.961808745079775
2003	27.42475369049548
2008	28.407512530949937
2009	24.909758004990536
2010	23.687057924378728
2011	26.089851415436293
2012	28.006923520160885
2013	24.101436344672457
2014	28.97781207175919
2015	28.77509747369548
2016	32.4440266095981
2017	33.28254289881956
2018	29.38234730326378
2019	30.846829713586
2020	31.55418359810081
2021	29.66650222841862
2022	31.80690240039895
