Year	U.S. dollars (Billions)
1980	-1.102
1981	-1.369
1982	-0.531
1983	-0.181
1984	0.039
1985	-0.455
1986	-1.365
1987	-0.676
1988	-0.572
1989	-0.588
1990	0.289
1991	-1.247
1992	-0.773
1993	-4.876
1994	-5.076
1995	-1.622
1996	-1.787
1997	-1.920
1998	-3.442
1999	-3.872
2000	-4.015
2001	-3.131
2002	-4.289
2003	-6.811
2004	-8.880
2005	-8.138
2006	-8.624
2007	-10.334
2008	-11.488
2009	-1.044
2010	0.256
2011	0.661
2012	1.993
2013	4.699
2014	1.701
2015	2.938
2016	5.765
2017	2.863
2018	0.255
2019	-1.337
2020	-1.762
2021	-7.702
2022	-14.645
2023	0.557
2024	-0.409
2025	-0.661
2026	-0.791
2027	-0.319
2028	-0.111
2029	0.389