Year	% of expense
2004	6.195303284708536
2005	0.8117279986656925
2006	4.745594707088947
2007	5.664937381626244
2008	22.436228903840757
2009	22.944055418198662
2010	20.253004756143213
2011	22.086436653793303
2012	19.73345703137851
2013	21.113198241045282
2014	15.024967938722694
2015	19.958900179675112
2016	15.195302150123858
2017	15.41568526777827
2018	14.671018207821195
2019	15.128901489293293
2020	18.082141506849027
2021	17.24572664879476
2022	18.094968242482963