Year current US$ 2000 2374.84557799 2001 2441.39334229 2002 2697.33069346 2003 3912.72142806 2004 4610.55827152 2005 4773.68406675 2006 4970.7501862 2007 5635.86792492 2008 6685.78220029 2009 6626.64934509 2010 6526.01934398 2011 6738.12502518 2012 6399.41003728 2013 6863.30054432 2014 7032.86452283 2015 5942.98080658 2016 6229.12858962 2017 6274.73250003 2018 6814.99129679 2019 6661.83371262 2020 6876.15504224 2021 7750.38898134