Year current US$ 2012 242443.904280663 2013 166490.450501442 2014 199149.996042252 2015 175449.997186661 2016 87659.9997282028 2017 176459.99789238002 2018 542553.067207336 2019 356730.01408577 2020 254748.404026031 2021 474599.987268448 2022 490869.343280792