Year % gross 1971 40.7347183227539 1972 40.7480583190918 1973 43.3974609375 1974 46.9658699035645 1975 54.0050010681152 1976 56.7307891845703 1977 56.37548828125 1978 53.895881652832 1980 52.8765182495117 1981 55.654670715332 1982 54.9518508911133 1983 56.0262489318848 1984 56.0324516296387 1985 57.475399017334 1986 57.8376617431641 1987 58.2615509033203 1988 59.0449485778809 1989 59.8694190979004 1990 62.358829498291 1991 61.2222518920898 1992 62.4943008422852 1993 61.7562408447266 1994 62.7655487060547 1995 64.1009902954102 1996 64.5792007446289 2018 49.2148895263672 2020 49.2616806030273