Year	% gross
1970	25.7861003875732
1971	34.4675598144531
1972	43.9938087463379
1973	53.8687591552734
1974	57.9808387756348
1975	57.2828216552734
1976	57.9116706848145
1977	56.954418182373
1978	52.994010925293
1979	47.4205589294434
1980	40.1661186218262
1981	36.623649597168
1982	32.5759811401367
1983	30.1066207885742
1984	29.8780403137207
1985	31.3204708099365
1986	32.6456489562988
1987	35.1279983520508
1988	37.2135391235352
1989	38.2257308959961
1990	39.0901184082031
1991	41.6763000488281
1992	44.5318794250488
1993	46.7970199584961
1994	47.0254516601562
1995	48.663631439209
1996	51.8940887451172
1997	54.2526817321777
1999	58.2373085021973
2000	59.2292213439941
2001	62.1108283996582
2002	62.8491706848145
2003	64.06201171875
2006	74.2114868164062
2007	78.3460006713867
2008	82.9210891723633
2009	88.7780380249023
2010	91.5271835327148
2011	92.9864196777344
2012	93.3106079101562