Year US Dollars 1960 -125688526.9287 1961 -162624721.09823 1962 -303570494.78689 1963 -32295301.26309 1964 -263891334.84445 1965 -239529908.63826 1966 -261531453.25472 1967 -340925099.11563 1968 -268361181.86667 1969 -426694519.46667 1970 -483733333.33333 1971 -386598979.30329 1972 -94829695.0772 1973 -582031572.85726 1974 -1143907201.10256 1975 -388430615.01514 1976 -2020016542.59719 1977 -1776052771.85501 1978 -1337903021.07134 1979 -1675917126.02167 1980 -320268280.13272 1981 870511272.70685 1982 548941481.44592 1983 1339967195.18863 1984 991058841.70481 1985 485542259.63535 1986 -175380051.90953 1987 2248147011.096 1988 4016786748.86727 1989 4265957155.75497 1990 7681220308.30883 1991 8657703431.56414 1992 10561620914.1664 1993 10779006462.1601 1994 9249913530.17011 1995 8712694559.47451 1996 10626519737.1825 1997 7561511090.92286 1998 5440693648.51958 1999 10677302829.6207 2000 11016070566.9854 2001 11766833277.2625 2002 12240110453.8488 2003 14819891616.1938 2004 14200397255.9296 2005 14557521386.0495 2006 11579504943.8353 2007 9254551132.50179 2008 12450324630.7448 2009 14446454886.3064 2010 22365455652.7073 2011 21997270523.5075 2012 19694342992.1349 2013 22702265672.6533 2014 24576537945.2885 2015 21971320903.6099 2016 19009559685.9315 2017 22930098870.8168