Year	million ton-km
1991	1.2000000477
1992	1.3999999762
1993	3
1994	3
1995	3.2000000477
1996	3.2999999523
1997	0.8000000119
1998	7.4000000954
1999	8.3999996185
2000	8.441
2001	7.388
2002	8.184
2003	7.583
2004	6.324
2005	6.069
2006	6.34
2007	5.364000000000001
2008	5.927
2009	2.562
2010	3.900821
2011	7.14949812767493
2012	9.49361123844254
2013	8.869308
2014	13.211711025
2015	7.843989
2016	8.02203384325573
2017	8.36736
2018	7.819001
2019	7.38543
2020	1.37475
2021	0.168685