Year	% of expense
1990	0.2392757591455142
1991	0.14595383534245096
1992	0.09550243232757334
1993	0.09117617262688683
1994	0.3631621187800963
1995	0.3833708497467642
1996	0.4171881518564873
1997	0.7588130718198505
1998	0.5539490645577118
1999	0.23230794131368238
2002	1.2363718107227155
2003	10.60852866034533
2004	16.109930585068707
2005	20.079953308272092
2006	0.04911708086097489
2007	10.421526170443517
2008	3.4157052301628554
2009	2.9934288211563227
2010	0.28747961008893835
2012	0.08028891364990556
2013	9.749558851811173
2014	8.375507255650586
2015	9.044024579374515
2016	11.860148081135403
2017	13.40054139889938
2018	12.045499036567236
2019	10.523648095624432
2020	7.197992034045152
2021	11.929950462933133
2022	10.460549649773473