Year % gross 1971 15.6356801986694 1973 15.7832403182983 1979 22.444860458374 1980 23.3184204101562 1981 24.380500793457 1982 24.7553405761719 1992 21.0164203643799 1995 23.4895401000977 1996 24.846549987793 1998 23.7418899536133 1999 25.4751796722412 2001 29.2852001190186 2002 26.9093608856201 2003 26.3219203948975 2004 25.8596305847168 2005 25.704719543457 2006 25.7298908233643 2008 25.9282493591309 2009 25.2506103515625 2010 26.1879997253418 2011 27.5550003051758 2012 28.1299991607666 2013 29.9750003814697 2014 31.6790008544922 2015 33.3810005187988 2016 35.4869995117188 2017 30.8290004730225 2018 25.6060009002686 2019 27.2390003204346 2020 28.871000289917 2021 29.7369995117188