Year % gross 1970 0.90583997964859 1971 0.98158997297287 1973 1.5905100107193 1975 1.64584994316101 1977 2.53615999221802 1978 2.53292989730835 1981 3.54137992858887 1983 2.99015998840332 1998 8.20098972320557 1999 10.5981597900391 2000 6.8549599647522 2017 12.5869998931885 2018 13.5640001296997 2019 13.1230001449585 2020 16.386999130249 2021 17.57200050354 2022 17.0321598052979