Year	million ton-km
2000	0
2001	0
2002	0.2
2003	0.21
2004	0.246
2005	0.253
2006	0.263
2007	0.279
2008	0.264
2009	0.448
2010	0.421937731663489
2011	0.483705822187223
2012	0.471
2013	0.635292
2014	0.922884
2015	0.538041372
2016	0.65910068
2017	0.530672
2018	0.690916
2019	0.318844
2020	0.510072
2021	0.358154