Year US Dollars adjusted for inflation) 1970 17000000 1974 2000000 1975 2000000 1977 0 1982 178000000 1983 46000000 1984 1000000 1985 29000000 1986 31000000 1988 15000000 1992 40000000 1993 40000000 1996 0 1997 0 2006 3000000 2009 20000000 2010 20000000