Year	% of expense
1995	5.88566506568193
1996	5.8599655324675135
1997	11.055142224587957
1998	12.448669447408413
1999	12.470743453278718
2000	11.761141643931008
2001	10.234214054898255
2002	9.978602291028142
2003	9.444263363754889
2004	7.973800087789699
2005	6.297469440589958
2006	5.167537562919796
2007	4.878887170200924
2008	4.574673958342414
2009	5.282774153372673
2010	4.77301799329562
2011	5.656534683724668
2012	6.071932202050762
2013	6.1705113959423254
2014	5.7274083840230885
2015	5.98744836905417
2016	7.207306289749509
2017	6.994083876119587
2018	6.438129693370123
2019	5.851354538870733
2020	4.862929600462091
2021	4.602554446851858
2022	4.062415313664047