Year	million ton-km
1974	2181.7999984322
1975	2527.4999953813017
1976	2957.1000314955004
1977	3192.7999902668007
1978	3574.5000004324
1979	3854.1000321584997
1980	4188.099976248896
1981	4666.200008817099
1982	4967.800033301101
1983	5372.2999580202
1984	6028.200049251702
1985	5993.300033696101
1986	6238.900057330898
1987	7119.1000287088
1988	7614.599975027003
1989	7808.100022532001
1990	8112.800062268601
1991	8247.699942126803
1992	9055.400088332
1993	9657.500054262799
1994	11116.299879230393
1995	11652.200102083501
1996	12005.800014383696
1997	13771.800119824702
1998	13461.599871374798
1999	14332.799914553692
2000	16088.205999999995
2001	15763.748000095362
2002	16554.821
2003	17845.63900000001
2004	20896.164999999997
2005	21653.50500000001
2006	22372.427000000003
2007	25959.034999999993
2008	26149.411000000004
2009	28582.926
2010	35016.66536056307
2011	34661.487324622474
2012	33943.58944418183
2013	35617.9107666909
2014	38364.494687083105
2015	39895.40909703711
2016	41619.05287551502
2017	47369.16188683476
2018	51466.346988990714
2019	53235.846687158875
2020	40575.88685011916
2021	48537.73381638901