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 0 1999 0 2000 0 2001 0 2002 0 2003 0 2004 0 2005 0 2006 0 2007 0 2008 0 2009 4331678.93403648 2010 14643505.0600495 2011 12845200.37074 2012 5070614.5460993 2013 5241611.04543984 2014 10676635.3456748 2015 4692906.60569435 2016 6370050.42930064 2017 12438099.682648 2018 13357187.387212 2019 7999887.74657668 2020 10332407.7234046 2021 28352633.8571112