Year	million ton-km
1996	2541
1997	2583
1998	2857
1999	3515
2000	4293
2001	5287
2002	6452
2004	8857
2006	9218.5
2007	8361
2008	8261
2009	7852
2010	10287
2011	11418
2012	12143
2013	12077
2014	12474
2015	11462.59
2016	12371
2017	13493
2019	17384
2020	18972
2021	18345