Year current US$ 2000 53.11489134071407 2001 60.20819128138089 2002 66.61336810797164 2003 82.31288342951268 2004 107.17984957511769 2005 119.91091296215218 2006 133.31136083378024 2007 168.78326137457574 2008 207.82322670467022 2009 188.4633543700849 2010 191.93491583246183 2011 209.50898163921457 2012 200.31163458728278 2013 204.75030698201255 2014 204.53896737803433 2015 181.51874038182834 2016 189.28595997352096 2017 208.28006873063742 2018 220.35227369031588 2019 224.55007426902256 2020 231.00645960481066 2021 276.90878347038654