Year current US$ 2001 421.810998724303 2002 460.94766930920713 2003 543.9958779493263 2004 604.5919524472583 2005 715.7710192675718 2006 768.9572989068939 2007 789.250466688363 2008 959.7281458594688 2009 951.1853635658964 2010 986.3436609627645 2011 1161.2650022267098 2012 1196.32106525655 2013 969.959980944962 2014 1278.1025750222736 2015 910.1589186621786 2016 1110.032372609025 2017 1277.3363520855573 2018 1424.1068579055568 2019 1476.2785764357848 2020 1689.787167254138 2021 1909.6189293073144