Year current US$ 2000 145000000 2001 250000000 2002 244000000 2003 383000000 2004 426000000 2005 362000000 2006 474000000 2007 541000000 2008 485000000 2009 507000000 2010 471000000 2011 516000000 2012 416000000 2013 357000000 2014 552000000 2015 540000000 2016 295000000 2017 449000000 2018 488000000 2019 451000000 2020 155000000