Year	million ton-km
1990	2.5
1991	2.5
1992	3.5
1993	4.5999999046
1994	6.5999999046
1995	8.5
1996	2.5999999046
1997	0.1000000015
1998	0.200000003
1999	0.200000003
2000	0.22
2001	0.183
2002	0.292
2003	0.312
2004	0.453
2005	0.327
2006	0.35
2007	0.35100000000000003
2008	0.35900000000000004
2009	0.347
2017	0.161087
2018	0.133837
2019	0.182569
2020	0.084844
2021	0.051408