Year	million ton-km
1970	5.9000000954
1971	3.0999999046
1972	4.6999998093
1973	6.3000001907
1974	6.8000001907
1975	6.5
1976	8.1000003815
1977	9.1999998093
1978	10.3000001907
1979	11.6999998093
1980	11.6999998093
1981	13.5
1982	16.6000003815
1983	17.2000007629
1984	19.5
1985	19.3999996185
1986	19.6000003815
1987	19.5
1988	22.8999996185
1989	41.5999984741
1990	53.9000015259
1991	59.2000007629
1992	100.5999984741
1993	129.6000061035
1994	136.3999938965
1995	173.3000030518
1996	192.1000061035
1997	236.3000030518
1998	265.5
1999	340.799987793
2000	407.769
2001	357.975
2002	396.021
2003	430.701
2004	502.302
2005	537.472
2006	571.977
2007	453.759
2008	420.794
2009	341.511
2010	357.885
2011	383.371
2012	322.104
2013	326.399
2014	369.955
2015	351.379
2016	387.739
2017	391.268
2018	373.511
2019	320.036527
2020	74.560823
2021	125.155714