Year US Dollars adjusted for inflation) 1967 1000000 1968 1000000 1969 0 1972 0 1973 2000000 1974 5000000 1975 3000000 1981 1000000 1982 2000000 1984 10000000 1985 7000000 1986 0 1991 34000000 1992 4000000 1994 3000000 1999 1000000 2000 1000000 2002 1000000 2004 1000000 2005 0 2012 75000000 2015 1000000 2016 6000000 2018 9000000 2022 20000000