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 0 1993 0 1994 0 1995 0 1996 0 1997 0 1998 699981.250452313 1999 457693.940228219 2000 753060.797092126 2001 699710.495705865 2002 1262472.85184266 2003 461406.661911859 2004 130541.764906027 2005 279323.395156057 2006 777379.629725532 2007 877982.930099727 2008 1107090.491503 2009 1349583.73946214 2010 1818458.31341182 2011 3138242.09231353 2012 2954848.92919389 2013 1991293.62967466 2014 1626477.02360798 2015 0 2016 0 2017 0 2018 0 2019 0 2020 0 2021 0