Year	U.S. dollars (Billions)
1980	-0.003
1981	0.002
1982	0.004
1983	0.005
1984	0.004
1985	0.003
1986	-0.001
1987	0.006
1988	-0.007
1989	-0.002
1990	-0.016
1991	-0.015
1992	-0.011
1993	-0.009
1994	-0.017
1995	-0.018
1996	-0.011
1997	-0.002
1998	-0.018
1999	-0.001
2000	-0.010
2001	-0.021
2002	-0.014
2003	-0.005
2004	-0.011
2005	-0.025
2006	-0.019
2007	-0.037
2008	-0.021
2009	-0.057
2010	-0.087
2011	-0.084
2012	-0.070
2013	-0.043
2014	-0.028
2015	-0.044
2016	-0.027
2017	-0.029
2018	-0.030
2019	-0.004
2020	-0.026
2021	-0.025
2022	-0.031
2023	-0.037
2024	-0.043
2025	-0.044
2026	-0.046
2027	-0.049
2028	-0.051
2029	-0.053