Year current US$ 2005 36873258675.8626 2006 38381291445.0148 2007 37268596756.8508 2008 26378895928.9012 2009 15096180538.3716 2010 17460756504.3316 2011 15714719573.6073 2012 14479604249.4888 2013 24674409653.7138 2014 33851272520.0209 2015 33478469645.5415 2016 36728723956.0926 2017 40971157840.6925 2018 44791955092.9842 2019 50766589677.4569 2020 45449569335.8292 2021 77032773200.5693