Year % gross 1971 0.65447998046875 1972 0.607179999351501 1974 0.515290021896362 1975 0.834450006484985 2001 11.7537002563477 2002 12.9744100570679 2003 12.8071804046631 2004 12.6182498931885 2005 12.6376695632935 2006 12.8377895355225 2007 13.7107601165771 2008 14.4537401199341 2009 16.5776805877686 2010 16.5874099731445 2011 16.1167392730713 2012 17.9646892547607 2013 18.0020198822021 2014 17.9062595367432 2015 17.7405395507812 2016 18.4300003051758 2017 18.7340297698975 2018 18.4706802368164 2019 18.4981594085693 2020 18.8139095306396 2021 17.4534893035889 2022 16.9224605560303