Year current US$ 2000 0.11162884626112908 2001 0.1578620183957107 2002 0.2335781526227764 2003 0.2755117579213268 2004 1.0053701560442634 2005 0.3223975198929135 2006 0.37613963853530363 2007 1.1199344992793576 2008 1.276375892833709 2009 0.5403972806422536 2010 0.5320155695474885 2011 0.7136469923307749 2012 0.6386125055236486 2013 0.7922738153180016 2014 0.9180491218647446 2015 0.7538840638077614 2016 0.8293953313151492 2017 0.9419657427179176 2018 0.9921485457124334 2019 0.9862105178820094 2020 0.9376009772883448 2021 3.0026763875913614