Year current US$ 2007 37000000 2008 43000000 2009 49000000 2010 46000000 2011 39000000 2012 39000000 2013 48000000 2014 47000000 2015 45000000 2016 66000000 2017 67000000 2018 68000000 2019 58000000 2020 30000000