Year	million ton-km
1970	4.1999998093
1971	4.8000001907
1972	4.5
1973	2.9000000954
1974	3.5
1975	5.4000000954
1976	4.6999998093
1977	3.9000000954
1978	3.5999999046
1979	5.0999999046
1980	2.7000000477
1981	15.1000003815
1982	14.3999996185
1983	1.7999999523
1984	3.9000000954
1985	4.3000001907
1986	9.3000001907
1987	14.8000001907
1988	14.1000003815
1989	14.3999996185
1990	2.7999999523
1991	3.5999999046
1992	5
1993	5.4000000954
1994	7
1995	8.8999996185
1996	18.2999992371
1997	32
1998	11.8999996185
1999	15
2000	21.985
2001	25.235
2002	22.207
2003	20.384
2004	34.461
2005	37.226
2006	35.883
2007	35.197
2008	38.458
2009	0
2010	71.894371680428
2011	66.8221755258011
2012	79.8959724316117
2013	147.711511102115
2014	134.10594055287
2015	121.567074708
2016	126.052370637
2017	45.776862
2018	64.710714
2019	94.840477
2020	73.431132
2021	150.327435