Year	million ton-km
1999	3671
2000	4078
2001	3942
2002	3766
2003	3853
2004	3904
2005	4322
2006	4312
2007	4329
2008	4556
2009	3962
2010	3919
2011	4178
2012	4768.056076
2013	4679.200692
2014	4492.652586
2015	4348.553709
2016	4189.628417
2017	3618.534146
2018	4217
2019	4545
2020	4131
2021	4444