Year gross (GPI) 1970 0.283360004425049 1971 0.284940004348755 1972 0.286080002784729 1973 0.285569995641708 1974 0.294050008058548 1975 0.307379990816116 1976 0.319160014390945 1977 0.343059986829758 1978 0.346520006656647 1979 0.359750002622604 1980 0.357950001955032 1981 0.369219988584518 1982 0.401279985904694 1983 0.394639998674393 1984 0.393739998340607 1985 0.4200100004673 1986 0.430860012769699 1987 0.430480003356934 1988 0.457080006599426 1989 0.464179992675781 1990 0.477209985256195 1991 0.487809985876083 1992 0.494340002536774 1993 0.504570007324219 1994 0.515179991722107 1995 0.527769982814789 1996 0.570169985294342 1997 0.582819998264313 1998 0.603330016136169 1999 0.623059988021851 2000 0.639039993286133 2001 0.663699984550476 2002 0.673569977283478 2003 0.661679983139038 2004 0.65777999162674 2005 0.69896000623703 2006 0.711939990520477 2007 0.69352000951767 2008 0.695930004119873 2009 0.701950013637543 2010 0.726490020751953 2011 0.777289986610413 2012 0.841939985752106 2013 0.909200012683868 2014 0.951070010662079 2015 0.94650000333786 2016 0.951759994029999 2017 0.973439991474152 2018 0.994859993457794 2019 1.03216004371643 2020 1.0464700460434 2021 1.03281998634338 2022 1.00817000865936