Year	current US$
1960	4000000
1961	3000000
1962	3000000
1963	3000000
1964	4000000
1965	4000000
1966	5000000
1967	6000000
1968	6000000
1969	6000000
1970	6000000
1971	7000000
1972	9000000
1973	11000000
1974	17000000
1975	17000000
1976	14000000
1977	20000000
1978	26000000
1979	29000000
1980	38000000
1981	40000000
1982	42000000
1983	38000000
1984	41000000
1985	41000000
1986	41000000
1987	48000000
1988	56000000
1989	54000000
1990	62000000
1991	59000000
1992	63000000
1993	61000000
1994	69000000
1995	77000000
1996	75000000
1997	73000000
1998	69000000
1999	73000000
2000	69000000
2001	73000000
2002	89000000
2003	94000000
2004	105000000
2005	121000000
2006	116000000
2007	143000000
2008	168000000
2009	145000000
2010	159000000
2011	193000000
2012	199000000
2013	198000000
2014	219000000
2015	209000000
2016	229000000
2017	231000000
2018	230000000
2019	238000000
2020	229000000
2021	246000000
2022	268000000
2023	265000000