Year US Dollars adjusted for inflation) 1961 3000000 1964 3000000 1965 0 1966 2000000 1968 4000000 1969 4000000 1970 1000000 1971 24000000 1973 2000000 1974 11000000 1975 34000000 1976 47000000 1977 28000000 1978 77000000 1980 33000000 1981 36000000 1982 5000000 1983 11000000 1984 98000000 1985 2000000 1986 7000000 1987 10000000 1988 22000000 1989 10000000 1990 29000000 2004 6000000 2006 20000000 2007 18000000 2010 27000000 2011 5000000 2012 1000000 2013 2000000 2015 5000000 2016 3000000 2019 26000000 2021 2000000