Year	current US$
1960	38000000
1961	21000000
1962	24000000
1963	79000000
1964	98000000
1965	108000000
1966	75000000
1967	61000000
1968	56000000
1969	85000000
1970	75000000
1971	85000000
1972	85000000
1973	104000000
1974	134000000
1975	172000000
1976	163000000
1977	168000000
1978	221000000
1979	254000000
1980	342000000
1981	369000000
1982	395000000
1983	464000000
1984	417000000
1985	453000000
1986	460000000
1987	571000000
1988	678000000
1989	582000000
1990	672000000
1991	737000000
1992	776000000
1993	890000000
1994	1155000000
1995	1333000000
1996	1398000000
1997	1693000000
1998	1246000000
1999	1422000000
2000	1573000000
2001	1473000000
2002	1419000000
2003	1754000000
2004	1938000000
2005	2283000000
2006	2492000000
2007	3122000000
2008	3590000000
2009	4384000000
2010	5133000000
2011	5774000000
2012	6066000000
2013	6571000000
2014	7590000000
2015	6652000000
2016	8935000000
2017	10345000000
2018	12712000000
2019	12340000000
2020	9856000000
2021	15893000000
2022	13735000000
2023	12476000000