Year current US$ 1990 2423519.79812414 1991 2689943.23691465 1992 2813147.63519432 1993 3084845.17010151 1994 2928737.16200859 1995 3057428.24503566 1996 3342633.49479562 1997 3642342.10376027 1998 3937404.47070452 1999 4082731.72670679 2000 4083554.47675847 2001 4075436.59231432 2002 4433607.60103868 2003 4832963.15001852 2004 5074360.3424941 2005 5351236.73084142 2006 5640471.53354551 2007 5150649.70313594 2008 5904302.69750898 2009 5799669.98569638 2010 5429866.02475186 2011 5369109.88517001 2012 5903309.1485742 2013 6141823.27241281 2014 5387320.99269108 2015 5563650.90821927 2016 5386733.35657269 2017 5986734.71751426 2018 5485024.41339119 2019 6116838.3594755 2020 5714555.433249 2021 5847876.77252899