Year	% of expense
1995	13.414511347676811
1996	10.72388595155801
1997	11.512834102095892
1998	11.056241492413275
1999	10.065025461615477
2000	8.469305127636046
2001	9.37926505023445
2002	8.739657483029532
2003	10.0854753295617
2004	8.571060033037833
2005	7.401287255730941
2006	6.921704161644743
2007	6.627368531196612
2008	6.316206758901949
2009	5.712439142298152
2010	5.644610106206209
2011	5.846268428236883
2012	5.887989305794812
2013	5.912942373529703
2014	5.920473653024427
2015	5.8621375075839355
2016	5.975051373764875
2017	6.0755508280470565
2018	5.938185227649383
2019	5.726849186009996
2020	5.208394408346367
2021	4.815637384839182
2022	5.230161243012529
