Year US Dollars adjusted for inflation) 1960 84000000 1961 107000000 1962 127000000 1963 137000000 1964 141000000 1965 171000000 1966 407000000 1967 327000000 1968 760000000 1969 1305000000 1970 1234000000 1971 1753000000 1972 1434000000 1973 2091000000 1974 2912000000 1975 5272000000 1976 4570000000 1977 5626000000 1978 3784000000 1979 533000000 1980 278000000 1981 487000000 1982 541000000 1983 509000000 1984 465000000 1985 548000000 1986 803000000 1987 833000000 1988 478000000 1989 192000000 1990 454000000 1991 1022000000 1992 432000000 1993 985000000 1994 446000000 1995 290000000 1996 611000000 1997 174000000 1998 377000000 1999 319000000 2000 414000000 2001 522000000 2002 433000000 2003 280000000 2004 119000000 2005 55000000 2006 421000000 2007 329000000 2008 60000000 2009 95000000 2010 95000000 2011 94000000 2012 40000000 2013 13000000 2014 13000000 2015 13000000 2016 413000000 2017 3000000 2018 3000000 2019 3000000 2020 2000000