Year	% of revenue
1972	1.4442605686775989
1973	1.3900709219858156
1974	1.288692356285534
1975	1.931284677763551
1976	1.5055338541666665
1977	1.4633799815301556
1978	1.1186550274814098
1979	1.0626163174641292
1980	1.1459170013386881
1981	1.1512542119056532
1982	0.563473649320517
1983	0.6098681068371358
1984	0.5327564495818669
1985	0.5452936306278015
1986	0.479559123546088
1987	0.4896713508096659
1988	0.5777310924369748
1989	0.5394534040073682
1990	0.5312328265250046
1991	0.4866459118466328
1992	0.7848213261678108
1993	0.9243791068047666
1994	0.8808479532163743