Year	million ton-km
2009	2.85
2010	6.34330383321339
2011	8.41823060991166
2012	8.43888748712717
2013	7.270032
2014	7.270032
2015	7.793474304
2016	9.718462457
2017	7.939983827
2018	10.34721
2019	1.72681
2020	2.72839
2021	3.31222