Year US Dollars adjusted for inflation) 1960 30000000 1961 15000000 1962 55000000 1963 39000000 1964 33000000 1965 55000000 1966 92000000 1967 126000000 1968 48000000 1969 238000000 1970 130000000 1971 68000000 1972 66000000 1973 87000000 1974 184000000 1975 372000000 1976 337000000 1977 464000000 1978 593000000 1979 279000000 1980 384000000 1981 401000000 1982 1061000000 1983 786000000 1984 478000000 1985 292000000 1986 250000000 1987 143000000 1988 247000000 1989 59000000 1990 16000000 1991 24000000 1993 1000000 1994 5000000 1995 19000000 1996 75000000 1997 77000000 1998 248000000 1999 63000000 2000 136000000 2001 160000000 2002 132000000 2003 281000000 2004 169000000 2005 49000000 2006 52000000 2007 183000000 2008 160000000 2009 234000000 2010 89000000 2011 214000000 2012 175000000 2013 75000000 2014 197000000 2015 231000000 2016 231000000 2017 369000000 2018 184000000 2019 229000000 2020 157000000 2021 67000000 2022 32000000