Year	U.S. dollars (Billions)
1980	0.015
1981	-0.027
1982	-0.056
1983	-0.173
1984	-0.118
1985	-0.032
1986	-0.049
1987	-0.030
1988	-0.037
1989	0.167
1990	-0.002
1991	-0.096
1992	-0.025
1993	0.021
1994	0.053
1995	0.063
1996	-0.063
1997	-0.092
1998	-0.183
1999	-0.090
2000	-0.009
2001	-0.281
2002	-0.201
2003	-0.087
2004	-0.138
2005	-0.147
2006	0.221
2007	0.325
2008	0.325
2009	0.111
2010	0.651
2011	0.431
2012	0.162
2013	-0.196
2014	-0.416
2015	-0.786
2016	-0.161
2017	0.069
2018	-0.119
2019	-0.448
2020	0.260
2021	0.176
2022	0.076
2023	0.089
2024	0.092
2025	0.085
2026	0.080
2027	0.079
2028	0.075
2029	0.074