Year	U.S. dollars (Billions)
1980	-0.016
1981	-0.017
1982	-0.009
1983	0.001
1984	-0.003
1985	0.002
1986	0.010
1987	0.011
1988	0.013
1989	0.014
1990	0.013
1991	-0.031
1992	-0.025
1993	-0.035
1994	0.004
1995	0.010
1996	0.011
1997	-0.009
1998	0.003
1999	-0.022
2000	-0.004
2001	-0.011
2002	-0.024
2003	-0.013
2004	-0.014
2005	-0.035
2006	-0.044
2007	-0.076
2008	-0.032
2009	-0.029
2010	-0.037
2011	-0.022
2012	-0.050
2013	-0.012
2014	-0.069
2015	-0.022
2016	-0.036
2017	-0.016
2018	0.007
2019	0.026
2020	0.005
2021	-0.122
2022	-0.094
2023	-0.045
2024	-0.021
2025	-0.024
2026	-0.027
2027	-0.028
2028	-0.028
2029	-0.028