Year million ton-km 1996 1.5 1997 7.8000001907 1998 0.8000000119 1999 2.0999999046 2000 2.227 2001 2.083 2002 2.313 2003 1.495 2004 1.75 2005 1.809 2006 1.88 2007 1.99 2008 1.886 2009 1.643 2014 0.011652 2015 0.015066036 2016 0.017582064 2018 0 2019 0 2020 0.004077 2021 0.002113