Year	million ton-km
1976	14.1999998093
1977	13.3999996185
1978	13.6000003815
1979	16
1980	20.8999996185
1981	33.2000007629
1982	20.7999992371
1983	46.2000007629
1984	25.1000003815
1985	33.2000007629
1986	24.7999992371
1987	25.6000003815
1988	26.8999996185
1989	51.5999984741
1990	39.9000015259
1991	41.5
1992	41.5
1993	28.7999992371
1994	55.5
1995	58.2999992371
1996	62.2000007629
1997	41.5
1998	38
1999	51.7999992371
2000	60.611
2001	50.818
2002	51.298
2003	56.455
2004	63.692
2005	68.112
2006	80.997
2007	72.88799999999999
2008	70.934
2009	64.323
2010	47.908
2011	50.973
2012	70.977
2013	70.431
2014	65.517
2015	46.043
2016	43.940435
2017	67.32035
2018	78.15964
2019	68.04358
2020	28.89977
2021	31.03638