Year current US$ 2000 429.56253052 2001 558.32427979 2002 581.97772217 2003 628.84716797 2004 650.58306885 2005 727.70440674 2006 782.64221191 2007 881.10369873 2008 1069.66259766 2009 1025.8807373 2010 1050.42126465 2011 1143.13793945 2012 1196.20715332 2013 1188.28283691 2014 1260.87524414 2015 1235.61889648 2016 1278.63244629 2017 1361.48278809 2018 1660.9864502 2019 1643.56970215 2020 1542.32263184 2021 1860.78369141