Year	% gross
1988	9.90209007263184
1989	10.6284198760986
1990	11.2355499267578
1991	11.8034000396729
1992	12.705530166626
1993	15.1801500320435
1994	17.2759609222412
2012	14.3233499526978
2013	14.9614601135254
2014	15.0038404464722
2015	15.5429096221924
2016	15.6052703857422
2017	17.5764808654785
2018	18.9430103302002
2019	19.2191791534424
2020	19.4924907684326
2021	19.3392601013184