Year % gross 1970 17.2226104736328 1971 17.4484596252441 1972 18.103609085083 1973 18.7627792358398 1974 19.4011402130127 1975 20.4494209289551 1976 21.1889705657959 1977 21.8313293457031 1978 22.6140594482422 1979 23.4813003540039 1980 24.4507293701172 1981 25.3782691955566 1982 26.5221099853516 1983 28.7667503356934 1984 29.251070022583 1985 30.3796100616455 1986 31.6326503753662 1987 32.3456802368164 1988 32.9146003723145 1989 33.5121307373047 1990 34.7712783813477 1991 36.1326904296875 1992 37.3950119018555 1993 38.7855491638184 1994 40.0356483459473 1995 40.9099006652832 1996 41.6803283691406 1997 43.0157508850098 1998 43.725341796875 1999 44.3392791748047 2000 45.8134613037109 2001 46.7887992858887 2002 48.5652809143066 2003 50.8860397338867 2004 51.9103698730469 2005 53.1930084228516 2006 54.6215286254883 2007 56.7114715576172 2008 58.449520111084 2009 59.4967002868652 2010 61.7938499450684 2011 64.246711730957 2012 66.1751480102539 2013 67.8004989624023 2014 70.8991394042969 2015 71.5841217041016 2016 72.7957534790039 2017 72.317138671875 2018 73.5309066772461 2019 73.9708023071289 2020 74.773681640625 2021 75.5998611450195 2022 76.5361633300781