Year US Dollars adjusted for inflation) 1977 1000000 1979 5000000 1980 3000000 1983 1000000 1985 0 1986 10000000 1989 8000000 1991 4000000 1998 5000000 2001 6000000 2004 1000000 2006 1000000 2017 1000000 2018 1000000 2019 1000000