Year current US$ 1993 3.584794379647606 1994 16.019559665310037 1995 26.403708839325997 1996 41.3350294515828 1997 48.65163314120857 1998 20.064299786455084 1999 15.657738093215485 2000 30.574305905597747 2001 63.03022878758371 2002 26.452346327973608