Year	% of expense
2000	0.5278585444060335
2001	5.456972717200817
2002	3.784806089481468
2003	9.803683730531592
2004	7.858187498862097
2010	1.6668232896107749
2011	1.8732209387900571
2012	1.999952896823186
2013	2.255612712123601
2014	2.381725113425202
2015	1.3697786945137964
2016	2.3427363826314047
2017	1.3939997878157846
2018	1.517249646480435
2019	1.0010202291292536
2020	1.3270480723109237
2021	1.0475606794065273