Year	% of expense
1985	5.390065518817614
1986	4.81729113033171
1987	4.668921130140722
1988	4.203424108232505
1989	5.786704170156282
1990	64.76390280561122
1994	64.15990351189103
1995	63.67897926634769
1996	62.96414261019015
1997	63.10645697559384
1998	47.77596254798956
1999	62.8976432390804
2000	62.9122474554513
2001	65.30869990904404
2002	64.93339693956185
2003	64.34206535059515
2004	66.3100277441523
2005	66.69324071093678
2006	65.59753699913654
2007	63.111047551704914
2008	61.19472453493394
2009	66.37917740498598
2010	67.86846494190294
2011	68.57173743838104
2012	68.898719723756
2013	68.73537086483113
2014	68.86298802215917
2015	68.78733925505449
2016	68.76633091532273
2017	69.27815692609641
2018	69.36197849712379
2019	69.55430876332932
2020	67.97508091402429
2021	71.4594211225776
2022	70.78501132793389