Year	current US$
2000	0
2001	0
2002	0
2003	0
2004	0
2005	0
2006	2
2007	1
2008	1
2009	1
2010	1
2011	1
2012	0
2013	1
2014	2
2015	2
2016	1
2017	4
2018	2
2019	2
2020	3
2021	7