Year	million ton-km
1970	11.6000003815
1971	12.3999996185
1972	15.3999996185
1973	14.6000003815
1974	14.5
1975	14.3000001907
1976	13.8999996185
1977	14
1978	15.1000003815
1979	15.1000003815
1980	12.1000003815
1981	11.8999996185
1982	13.6000003815
1983	13.6999998093
1984	13.5
1985	17.2000007629
1986	17
1987	16.2999992371
1988	17.2000007629
1989	17.2999992371
1990	15
1991	22.3999996185
1992	26.1000003815
1993	24
1994	21.7999992371
1995	25.6000003815
1996	22.2000007629
1997	23.1000003815
1998	24.7000007629
1999	26.2000007629
2000	32.224
2001	25.98
2002	27.317
2003	36.231
2004	40.565
2005	38.757
2006	39.363
2007	32.61
2008	27.174
2009	22.379
2010	17.987
2011	16.721
2012	11.102
2013	19.929
2014	30.81553
2015	26.71765
2016	25.294469
2017	27.81465
2018	25.22637
2019	22.73254
2020	4.323665454
2021	0.47308