Year	U.S. dollars (Billions)
1980	1.246
1981	0.641
1982	0.513
1983	0.451
1984	0.635
1985	0.374
1986	-0.948
1987	-0.266
1988	-0.602
1989	-0.177
1990	0.150
1991	0.091
1992	-0.226
1993	-0.058
1994	0.336
1995	0.465
1996	0.889
1997	0.531
1998	-0.621
1999	0.390
2000	1.001
2001	0.517
2002	0.338
2003	0.766
2004	0.924
2005	1.983
2006	1.484
2007	2.748
2008	3.830
2009	0.804
2010	2.453
2011	2.604
2012	1.978
2013	1.463
2014	1.112
2015	0.141
2016	-0.759
2017	-0.105
2018	1.202
2019	0.776
2020	-0.076
2021	0.674
2022	2.198
2023	0.856
2024	0.840
2025	0.629
2026	0.461
2027	0.336
2028	0.211
2029	0.122