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