Year	current US$
1960	17000000
1961	20000000
1962	20000000
1963	22000000
1964	24000000
1965	25000000
1966	32000000
1967	33000000
1968	33000000
1969	33000000
1970	32000000
1971	39000000
1972	56000000
1973	88000000
1974	120000000
1975	164000000
1976	212000000
1977	234000000
1978	281000000
1979	328000000
1980	464000000
1981	516000000
1982	524000000
1983	485000000
1984	441000000
1985	343000000
1986	354000000
1987	469000000
1988	587000000
1989	617000000
1990	672000000
1991	813000000
1992	899000000
1993	870000000
1994	879000000
1995	1107000000
1996	1126000000
1997	1140000000
1998	941000000
1999	866000000
2000	809000000
2001	743000000
2002	815000000
2003	1121000000
2004	1440000000
2005	1410000000
2006	1500000000
2007	1738000000
2008	1800000000
2009	1850000000
2010	2300000000
2011	2500000000
2012	2602000000
2013	2175000000
2014	2207000000
2015	1997000000
2016	1861000000
2017	2066000000
2018	2185000000
2019	1734000000
2020	1380000000
2021	1824000000
2022	1856000000
2023	1772000000