Year	% of expense
1974	2.8214024835646456
1975	2.0977637047298634
1976	1.872146118721461
1977	1.7602534765006161
1978	2.1910570684899575
1979	2.9346976479783984
1980	2.9568866844715758
1981	3.3401119870741285
1982	3.200449185850646
1983	3.141901655588126
1984	2.987554801301089
1985	3.0709648389792377
1986	2.821426999427792
1987	2.3948352021746517
1988	2.509613180880593
1989	2.1799532430017505
1990	62.851544359999544
1991	65.15060178352424
1992	66.16039058345821
1993	67.29144691171035
1994	66.5445321307779
1995	64.13108242303873
1996	66.14998614659976
1997	67.20420776202299
1998	70.76423592322628
1999	65.62567687309246
2000	66.02400256228294
2001	67.995247995248
2002	68.67442082085698
2003	69.25972214148695
2004	70.35741403622953
2005	70.4336721749573
2006	69.64498087493169
2007	68.90442242538519
2008	69.28682959472458
2009	71.28445670503592
2010	69.24801690404485
2011	68.70764716888527
2012	67.3170433034507
2013	67.1383722888447
2014	67.77855300787957
2015	67.6235061364865
2016	67.54050870302856
2017	67.56912060940206
2018	67.24480862328394
2019	66.94569780672501
2020	70.07302070198614
2021	73.08312740756847
2022	69.40063140421505