Year current US$ 2000 0 2001 0 2002 0 2003 0 2004 0 2005 0 2006 0.11445876 2007 0.0067727 2008 0.08662228 2009 0.09781266 2010 0.08899115 2011 0.02018179 2012 0.01650955 2013 0.03187669 2014 0.02790073 2015 0.01608491 2016 0 2017 0 2018 0 2019 0 2020 0 2021 0 2022 0