Year US Dollars adjusted for inflation) 1961 3000000 1962 10000000 1963 4000000 1966 1000000 1967 10000000 1969 2000000 1971 15000000 1975 11000000 1976 89000000 1981 91000000 1982 4000000 1983 15000000 1984 13000000 1985 0 1988 2000000 1990 1000000 1994 0 1997 9000000 1998 4000000 2000 7000000 2002 1000000 2003 3000000 2005 13000000 2007 8000000 2008 3000000 2009 10000000 2011 0 2012 9000000 2013 6000000 2014 1000000 2016 21000000 2017 31000000 2018 25000000 2019 18000000 2020 44000000 2021 36000000 2022 58000000