Year	% of expense
1990	4.51182271361151
1991	0.24061959545830514
1992	5.61741106905126
1993	5.844095644918596
1994	4.597341673182174
1996	2.7861499394831144
1997	1.737060491601554
1998	1.078928476205782
1999	2.0791467557412417
2000	2.2167319233333904
2001	2.0859392893007525
2002	4.356731861433706
2003	6.001780167225204
2004	6.754172605582699
2005	6.131140708988228
2006	5.8465091523906425
2007	6.311568758486256
2008	4.660972771307727
2009	5.672078849033256
2010	6.599526605158894
2011	8.604898511035179
2012	5.353302107097123
2013	4.508294863268817
2014	4.348501727364059
2015	5.7530716466831455
2016	5.610134820507643
2017	6.2547276924133755
2018	7.060909060820906
2019	10.463878435763114
2020	10.370211683343864
2021	9.54445353822253
2022	9.969504135205899