Year	million ton-km
1970	9.3000001907
1971	9.1999998093
1972	8.6000003815
1973	8.1000003815
1974	9.1999998093
1975	8.8999996185
1976	13.1999998093
1977	18.2999992371
1978	18.8999996185
1979	22
1980	22.3999996185
1981	20.8999996185
1982	21.5
1983	21
1984	24
1985	25.2999992371
1986	24.7999992371
1987	30
1988	33.0999984741
1989	32.7000007629
1990	38.7000007629
1991	36.0999984741
1992	36.2000007629
1993	37.9000015259
1994	43.4000015259
1995	43.7999992371
1996	44.9000015259
1997	54.5
1998	90.5
1999	84.8000030518
2000	79.005
2001	22.948
2002	12.506
2003	9.735
2004	10.173
2005	10.351
2006	10.04
2007	10.241
2008	10.63
2009	9.099
2010	15.6977120470821
2011	16.867234240556
2012	15.744
2013	13.537781
2014	11.8182973850146
2015	9.28416
2016	6.027344
2017	10.552031
2018	11.13032
2019	10.8
2020	1.613892
2021	2.16644