Year	current US$
2000	0.21591138
2001	1.34768766
2002	4.38023966
2003	0.89638271
2004	19.51307858
2005	4.62351368
2006	1.47984713
2007	1.30606856
2008	6.87708755
2009	2.2505049
2010	3.09710368
2011	6.97807125
2012	7.09585381
2013	6.31087195
2014	6.7666975
2015	4.32904273
2016	3.54634758
2017	6.61789519
2018	3.40863987
2019	2.31135199
2020	2.49907874
2021	13.15975822