Year current US$ 2007 401615770.100117 2008 467637662.100303 2009 387987108.003343 2010 391444037.267804 2011 436051398.11219 2012 316540099.394092 2013 338892223.911167 2014 293925483.552574 2015 282147352.563711 2016 372579216.243566 2017 353353477.578747 2018 464808305.277137 2019 486210367.953961 2020 385375491.160309 2021 402433323.580482