Year current US$ 2008 6447307 2009 4303754 2010 2935421 2011 4141872.0000000005 2012 4638187 2013 4359115 2014 3313970 2015 552512 2016 2140177 2017 2485946 2018 4123124 2019 2128180 2020 1133039 2021 1034853.0000000001 2022 927489