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 828346.982327406 1993 253835.658985756 1994 1890792.76252066 1995 3794593.39773593 1996 3313617.62854076 1997 3265828.46353247 1998 2371425.11319474 1999 3794158.31978289 2000 4002345.52454552 2001 3319416.29825291 2002 7946919.7937734 2003 6192937.13805086 2004 5848213.87877314 2005 5057441.63742016 2006 10261469.9244257 2007 12547717.9919979 2008 15214130.1966424 2009 16044336.9503061 2010 44459994.012085 2011 73020331.0186722 2012 71361375.1340308 2013 59442183.5455668 2014 76592880.168516 2015 78630894.6603293 2016 130444146.079635 2017 130769929.78395 2018 173061038.622652 2019 239006856.890949 2020 227295854.966617 2021 474745373.311037