Year	% of expense
2005	6.625988312134755
2006	5.521478948493268
2007	4.96975059171643
2008	3.833026795132056
2009	3.111439431487381
2010	2.266497599685064
2011	1.5349930353443184
2012	1.121534579505928
2013	1.741394277280706
2014	2.0879065108872634
2015	3.1964661409415394
2016	3.6484368264610523
2017	4.026578345854984
2018	4.166045709778446
2019	4.072574281805249
2020	5.768244590374049
2021	6.539078677881753
2022	7.459943968274492