Year	current US$
2004	4428000000
2005	9087000000
2006	12979000000
2007	20170000000
2008	15129000000
2009	20419000000
2010	21135000000
2011	17271000000
2012	17023000000
2013	17660000000
2014	24118000000
2015	19346000000
2016	16658000000
2017	17552000000
2018	16651000000
2019	15140000000
2020	8533000000