Year % gross 1971 12.3765296936035 1972 13.6393203735352 1973 19.3162403106689 1974 20.6553592681885 1975 22.076000213623 1976 24.9288597106934 1977 25.2194805145264 1978 27.2564296722412 1979 25.1319198608398 1980 26.004940032959 1981 25.3823795318604 1982 25.1386909484863 1983 24.8741207122803 1984 25.7862892150879 1985 26.8239994049072 1986 28.4620208740234 1987 29.5593299865723 1988 31.068920135498 1989 33.1608695983887 1990 34.5054016113281 1991 35.7718811035156 1992 37.5704002380371 1993 38.7177886962891 1994 41.6383895874023 1995 41.5711898803711 1996 43.0498886108398 1997 45.595630645752 1998 47.7561492919922 1999 50.1824188232422 2000 53.6866607666016 2001 56.6614418029785 2002 58.3453483581543 2003 59.9459686279297 2004 60.8302307128906 2005 61.5280685424805 2006 62.1047286987305 2007 62.1660003662109 2008 62.2284812927246 2009 63.9721183776855 2010 68.6996612548828 2011 72.6763305664062 2012 75.0640411376953 2013 77.2431564331055 2014 80.0947265625 2015 80.9930191040039 2016 81.8702621459961 2017 83.5683212280273 2018 83.391242980957 2019 82.0160980224609 2020 81.020622253418 2021 83.7875823974609