Year current US$ 2000 3019000000 2001 3321000000 2002 3651000000 2003 3956000000 2004 4472000000 2005 6186000000 2006 8827000000 2007 11273000000 2008 13288000000 2009 10347000000 2010 11818000000 2011 13206000000 2012 15072000000 2013 16188000000 2014 15848000000 2015 16637099609.375 2016 17127259765.625 2017 17644699218.75 2018 18004099609.375 2019 18382000000 2020 15085000000