Year current US$ 2000 38.565448107851026 2001 39.71629069161746 2002 44.27934701424433 2003 50.564275261748534 2004 56.8764312432401 2005 65.32057903630957 2006 74.91241640574194 2007 89.58813110056178 2008 117.06528819761155 2009 139.0903895708793 2010 161.0365410751021 2011 201.15696798503876 2012 234.5371801435921 2013 265.07732133135835 2014 288.75291663872355 2015 308.6680148313238 2016 313.93475555348175 2017 344.21916276092804 2018 390.172054525948 2019 416.3777017803679 2020 448.0166774065803 2021 515.7439182284081