Year	U.S. dollars (Billions)
1980	-1.064
1981	-4.686
1982	-3.258
1983	-1.632
1984	-0.623
1985	0.380
1986	1.166
1987	0.435
1988	-1.066
1989	0.153
1990	-0.181
1991	-0.716
1992	-0.184
1993	0.233
1994	-2.196
1995	-0.132
1996	-5.507
1997	-7.161
1998	-9.369
1999	-11.315
2000	-12.810
2001	-12.707
2002	-11.292
2003	-10.958
2004	-15.062
2005	-18.918
2006	-21.419
2007	-23.138
2008	-31.166
2009	-25.158
2010	-24.442
2011	-14.650
2012	-3.491
2013	3.704
2014	0.364
2015	0.459
2016	2.419
2017	2.865
2018	1.344
2019	1.044
2020	-2.377
2021	-1.936
2022	-2.932
2023	3.945
2024	4.691
2025	4.703
2026	4.704
2027	3.871
2028	3.376
2029	3.038