Year	% of tax revenue
1972	20.795660036166392
1973	19.79320531757751
1974	19.650067294750954
1975	18.291347207009874
1976	18.634538152610443
1977	15.966964900206468
1978	10.12433392539963
1979	10.325534079348941
1980	12.246489859594387
1981	14.795447554598576
1982	13.126252505010028
1983	10.12823299282766
1984	9.643404907975457
1985	9.813596491228065