Year US Dollars adjusted for inflation) 1960 28000000 1961 52000000 1962 108000000 1963 108000000 1964 93000000 1965 87000000 1966 58000000 1967 140000000 1968 88000000 1969 124000000 1970 250000000 1971 243000000 1972 147000000 1973 338000000 1974 113000000 1975 87000000 1976 148000000 1977 104000000 1978 191000000 1979 306000000 1980 322000000 1981 350000000 1982 82000000 1983 254000000 1984 351000000 1985 188000000 1986 162000000 1987 534000000 1988 618000000 1989 285000000 1990 235000000 1991 580000000 1992 426000000 1993 183000000 1994 610000000 1995 530000000 1996 734000000 1997 935000000 1998 76000000 1999 172000000 2000 85000000 2001 116000000 2002 152000000 2003 131000000 2004 120000000 2005 115000000 2006 99000000 2007 8000000 2008 16000000 2009 63000000 2010 60000000 2011 249000000 2012 278000000 2013 378000000 2014 105000000 2015 180000000 2016 342000000 2017 326000000 2018 634000000 2019 278000000 2020 145000000 2021 146000000 2022 113000000