Year current US$ 1970 3298533.74020295 1971 1826594.7621791 1972 1668207.35365245 1973 3134303.95885133 1974 9044938.47562948 1975 3380744.9101113 1976 3785131.44844398 1977 3511983.9602842 1978 2693463.31048025 1979 5708645.98301407 1980 4334572.95865517 1981 2041370.05653524 1982 1750085.18917197 1983 2059735.60713726 1984 1368719.68198836 1985 1474609.05639456 1986 771929.810996945 1987 1666806.33361548 1988 11215733.3859785 1989 10285206.2236687 1990 4005328.2858001 1991 1384370.66725073 1992 1693104.58755085 1993 1508902.89795025 1994 2585032.97467242 1995 1139462.63288072 1996 1422019.54800253 1997 703963.315544278 1998 0 1999 0 2000 0 2001 0 2002 0 2003 0 2004 0 2005 0 2006 0 2007 0 2008 0 2009 0 2010 0 2011 0 2012 0 2013 0 2014 0 2015 0 2016 0 2017 0 2018 0 2019 0 2020 0 2021 0