Year current US$ 1998 20000 1999 300000 2000 400000 2001 1320000 2002 1720000 2003 8109999.999999999 2004 9440000 2005 5130000 2006 9920000 2007 17590000 2008 52350000 2009 39210000 2010 24460000 2011 21220000 2012 21330000 2013 12110000 2014 13830000 2015 11500000 2016 10420000 2017 12760000 2018 15910000 2019 18180000 2020 17630000 2021 20300000 2022 20730000