Year	gross (GPI)
1978	0.866590023040771
1979	0.885269999504089
1980	0.894869983196259
1981	0.898530006408691
1982	0.902679979801178
1983	0.904399991035461
1984	0.904550015926361
1985	0.909539997577667
1986	0.913429975509644
1987	0.91865998506546
1988	0.924639999866486
1989	0.933790028095245
1990	0.935999989509583
1991	0.942229986190796
1992	0.942380011081696
1993	0.925719976425171
1994	0.932519972324371
1995	0.936720013618469
1996	0.942770004272461
1998	0.919160008430481
1999	0.928799986839294
2000	0.9375
2001	0.949519991874695
2002	0.943650007247925
2003	0.940460026264191
2004	0.935320019721985
2005	0.940559983253479
2006	0.942879974842072
2007	0.948230028152466
2008	0.953610002994537
2009	0.959029972553253
2010	0.97052001953125
2011	0.974889993667603
2012	0.971909999847412
2013	0.975489974021912
2015	0.9653599858284
2016	0.962459981441498
2017	0.956870019435883
2018	0.951099991798401
2019	0.946449995040894
2020	0.94744998216629