Year % gross 1970 18.8758506774902 1971 20.8325099945068 1972 24.7942008972168 1973 28.3904209136963 1974 31.5209503173828 1975 34.2298889160156 1976 34.7105293273926 1977 36.4374504089355 1998 46.0514297485352 1999 45.7177696228027 2000 43.8961181640625 2001 44.007381439209 2002 44.2733688354492 2003 43.7323608398438 2004 48.4555892944336 2005 49.7005195617676 2006 53.6245994567871 2007 61.1017417907715 2009 59.6640014648438 2010 65.4768905639648 2011 69.6596221923828 2012 72.8746337890625 2013 74.9233322143555 2014 77.6130981445312 2015 79.9569091796875 2016 86.6399230957031