Year current US$ 2000 0.13357644 2001 0.15227576 2002 0.25087791 2003 0.32555222 2004 0.83273476 2005 0.96689122 2006 0.5404608 2007 0.62801632 2008 1.17768488 2009 0.66663331 2010 0.23982568 2011 1.36762545 2012 0.99489021 2013 0.86006572 2014 0.95263744 2015 0.46969178 2016 1.05423648 2017 0.7524262 2018 0.85683021 2019 1.33995787 2020 0.66001701