Year	U.S. dollars (Billions)
1980	-0.117
1981	-0.147
1982	-0.041
1983	-0.019
1984	-0.051
1985	-0.030
1986	0.094
1987	0.065
1988	-0.056
1989	-0.104
1990	-0.119
1991	-0.017
1993	-0.092
1994	-0.232
1995	-0.022
1996	0.034
1997	-0.089
1998	0.003
1999	-0.124
2000	-0.034
2001	0.276
2002	0.249
2003	0.095
2004	-0.116
2005	-0.324
2006	-0.612
2007	-0.423
2008	-0.971
2009	-0.656
2010	-1.006
2011	-1.538
2012	-0.827
2013	-0.750
2014	-0.690
2015	-0.417
2016	-0.491
2017	-0.612
2018	-0.555
2019	-0.718
2020	-1.003
2021	-1.497
2022	-1.486
2023	-0.844
2024	-0.868
2025	-0.852
2026	-0.854
2027	-0.907
2028	-0.960
2029	-1.023