Year	% gross
1970	0.676519989967346
1974	1.82097005844116
1975	3.56235003471375
1979	2.36628007888794
1981	2.30222010612488
1982	2.31761002540588
1988	3.16499996185303
1989	2.95483994483948
1998	3.39847993850708
1999	3.37210011482239
2011	5.84504985809326
2012	4.55194997787476