Year	gross (GPI)
1971	0.37635999917984
1972	0.402909994125366
1973	0.456380009651184
1974	0.490929991006851
1975	0.523769974708557
1976	0.578790009021759
1977	0.636669993400574
1978	0.681559979915619
1979	0.693750023841858
1980	0.735040009021759
1981	0.791459977626801
1982	0.84113997220993
1983	0.897849977016449
1984	0.955860018730164
1985	0.962430000305176
1986	1.00416004657745
1987	1.01988995075226
1988	1.04922997951508
1989	1.04168999195099
1990	1.07087004184723
1991	1.08512997627258
1992	1.09189999103546
1993	1.10817003250122
1994	1.08245003223419
1995	1.13629996776581
1996	1.14647996425629
1997	1.14962995052338
1998	1.15713000297546
1999	1.15626001358032
2000	1.15269005298615
2001	1.13567996025085
2002	1.15925002098083
2003	1.16041994094849
2004	1.18292999267578
2005	1.18050003051758
2006	1.18467998504639
2007	1.18885004520416
2008	1.19131004810333
2009	1.19298005104065
2010	1.1865199804306
2011	1.18502998352051
2012	1.17613995075226
2013	1.17466998100281
2014	1.16842997074127
2015	1.16105997562408
2016	1.16592001914978
2017	1.1698100566864
2018	1.17788004875183
2019	1.18435001373291
2020	1.20201003551483
2021	1.21069002151489