Year	US Dollars adjusted for inflation)
1961	7000000
1962	61000000
1963	85000000
1964	177000000
1965	350000000
1966	437000000
1967	524000000
1968	57000000
1969	79000000
1970	14000000
1971	14000000
1972	180000000
1973	110000000
1974	13000000
1975	56000000
1976	130000000
1977	1048000000
1978	1264000000
1979	1823000000
1980	1342000000
1981	1386000000
1982	1357000000
1983	697000000
1984	656000000
1985	368000000
1986	146000000
1987	367000000
1988	319000000
1989	455000000
1990	733000000
1991	1035000000
1992	23000000
1993	22000000
1994	186000000
1995	299000000
1996	83000000
1997	37000000
1998	98000000
1999	370000000
2000	402000000
2001	539000000
2002	249000000
2003	195000000
2004	242000000
2005	159000000
2006	340000000
2007	507000000
2008	1517000000
2009	1070000000
2010	831000000
2011	1132000000
2012	660000000
2013	361000000
2014	710000000
2015	894000000
2016	2911000000
2017	1133000000
2018	1282000000
2019	167000000
2020	675000000
2021	237000000
2022	158000000