Year current US$ 2008 8353730 2009 6989321 2010 9180496 2011 5739492 2012 8248200.000000001 2013 5593277 2014 24227835 2015 15626132 2016 10502624 2017 7925744 2018 9903650 2019 44073889 2020 43185591 2021 24782074 2022 9014081