Year current US$ 1995 10000000 1996 13000000 1997 16000000 1998 8000000 1999 9000000 2000 7000000 2001 6800000.19073486 2002 5900000.09536743 2003 10300000.1907349 2004 12800000.1907349 2005 14899999.6185303 2006 15699999.8092651 2007 14399999.6185303 2008 17500000 2009 17899999.6185303 2010 16200000.7629395 2011 31399999.6185303 2012 38200000.762939505 2013 44400001.5258789 2014 36000000 2015 43299999.237060495 2016 51299999.237060495 2017 48200000.762939505 2018 48000000 2019 56900001.5258789 2020 47000000