Year % gross 1970 3.40041995048523 1971 3.4376699924469 1972 3.7318799495697 1973 4.11269998550415 1974 4.42645978927612 1975 4.85213994979858 1976 5.43185997009277 1977 5.83308982849121 1978 6.19754981994629 1979 6.51667022705078 1980 6.95031976699829 1981 7.50263023376465 1982 7.85731983184814 1983 8.13545989990234 1984 8.45584011077881 1985 8.66679954528809 1986 8.88004970550537 1987 9.01945018768311 1988 9.5523099899292 1989 9.59185028076172 1990 9.94318962097168 1991 10.0425796508789 1992 10.7116203308105 1993 11.659649848938 1994 12.2323999404907 1995 13.0774202346802 1996 14.2200202941895 1997 15.2658004760742 1998 16.3491191864014 1999 17.8397598266602 2000 18.4357891082764 2001 19.3491897583008 2002 20.1395301818848 2003 21.0756607055664 2004 22.3334293365479 2005 23.6661796569824 2006 24.944299697876 2007 26.3760890960693 2008 29.2887306213379 2009 29.5948104858398 2010 31.241870880127 2011 32.0437316894531 2012 34.1855583190918 2013 35.3806915283203 2014 37.9222412109375 2015 40.2323112487793 2016 40.7547302246094 2017 41.2599105834961 2018 42.2356109619141 2019 42.6380081176758 2020 42.611888885498 2021 42.549919128418 2022 42.746509552002