Year million ton-km 1984 0.3000000119 1985 0.400000006 1986 1.5 1987 1.7000000477 1988 2 1989 4.5 1990 10.3999996185 1991 9.1000003815 1992 14.8999996185 1993 10.6000003815 1994 10.5 1995 12.8000001907 1996 16.7000007629 1997 24.2000007629 1998 17.1000003815 1999 19.7000007629 2000 19.883 2001 22.009 2002 28.235 2003 21.348 2004 24.123 2005 25.812 2006 30.716 2007 27.644 2008 26.709 2009 25.623 2010 36.289 2011 31.922 2012 6.478 2013 26.245992 2014 32.310996 2015 19.234992 2016 20.123 2017 29.345 2018 7.793 2019 2.40769 2020 0.75756 2021 0.79776