Year current US$ 1970 0 1971 0 1972 0 1973 0 1974 0 1975 0 1976 0 1977 0 1978 0 1979 0 1980 0 1981 0 1982 0 1983 0 1984 0 1985 0 1986 0 1987 0 1988 0 1989 0 1990 0 1991 0 1992 595231.197040528 1993 428308.151650077 1994 3985129.56370475 1995 5215472.60312176 1996 2838339.0122425 1997 2856003.40347921 1998 1051136.51678089 1999 1683595.46213697 2000 3134379.64085196 2001 3661650.92332574 2002 10877393.5615117 2003 105539.586302688 2004 0 2005 0 2006 0 2007 0 2008 0 2009 1788145.5419792 2010 126037735.997118 2011 155223016.275779 2012 70276986.8651392 2013 56202602.1462069 2014 4268983.3886976 2015 28458011.7081822 2016 0 2017 0 2018 52325780.498965 2019 130329815.17033 2020 104758273.295265 2021 448080809.990757