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 5828725.45142663 1998 1591108.94794549 1999 2603090.16509234 2000 3107028.1839228 2001 1146978.80336734 2002 3190956.36070199 2003 3826618.98037795 2004 9791003.71040899 2005 15857756.2799775 2006 23258205.6135532 2007 22801172.5193253 2008 20768666.1375656 2009 24948644.2915878 2010 27813801.0241219 2011 37642329.7104218 2012 38076582.7539422 2013 27228269.8007193 2014 17298342.8653893 2015 10257414.7713037 2016 10738559.8286509 2017 10233137.4869843 2018 4078193.0792844 2019 0 2020 0 2021 5605341.85192125