Year	% gross
1971	2.90303993225098
1972	3.00874996185303
1973	3.00875997543335
1974	3.04820990562439
1975	3.05502009391785
1976	5.10861015319824
1977	5.30795001983643
1978	5.44545984268188
1979	5.42182016372681
1980	5.18916988372803
1981	4.84697008132935
1982	5.1585898399353
1983	4.32762002944946
1984	4.90748977661133
1985	5.81113004684448
1986	7.02504014968872
1987	7.07786989212036
1989	8.25224018096924
1991	7.29698991775513
1992	7.82292985916138
1993	8.23814010620117
1999	4.71947002410889
2000	4.45705986022949
2001	4.76421022415161
2002	6.65847015380859
2003	6.49900007247925
2004	10.1601696014404
