Year	% of expense
1985	1.0051436930772497
1986	1.8381037567084078
1987	1.8137440558851998
1988	5.075528700906345
1989	3.452112169104414
1990	44.93661265314808
1991	39.39291260765213
1992	38.199757294359735
1993	37.371993188958434
1994	36.2601186047036
1995	35.579943783068785
1996	33.66531254095138
1997	37.382464175427636
1998	37.531930028777445
1999	36.49490916056404
2004	32.07835537619371
2005	33.6283185840708
2006	35.54514790048103
2007	37.152314836099485
2008	40.57232146404121
2009	39.20130548781606
2010	40.92068285014731
2011	44.37396543138988
2012	46.20061643039507