Year	million ton-km
1970	4.8000001907
1971	6.1999998093
1972	5.3000001907
1973	7.1999998093
1974	7.3000001907
1975	11
1976	17.6000003815
1977	22.6000003815
1978	22.5
1979	30.3999996185
1980	25.6000003815
1981	30.3999996185
1982	38.7999992371
1983	33.9000015259
1984	30.7000007629
1985	36.2000007629
1986	43.9000015259
1987	50.9000015259
1988	48.7999992371
1989	34
1990	31.5
1991	55.9000015259
1992	56.5999984741
1993	53.2999992371
1994	49.2999992371
1995	57.7000007629
1996	57
1997	53.9000015259
1998	58
1999	57.7999992371
2000	62.545
2001	62.97
2002	51.185
2003	52.553
2004	61.898
2005	60.764
2006	50.626
2007	44.809
2008	55.478
2009	62.807
2010	64.571
2011	40.9843170717889
2012	38.8408635811992
2013	43.321464
2014	47.000251
2015	52.913598
2016	53.82625368
2017	77.93581
2018	97.71152
2019	102.19214
2020	46.244684
2021	58.894368