Year	Tonnes
1905	14668
1909	172349
1910	370367
1911	605055
1912	898415
1913	1239446
1914	1727157
1915	2335879
1916	2841925
1918	3340637
1919	3931024
1920	4697427
1921	5522502
1922	6365912
1923	7374337
1924	8434100
1925	10124587
1926	11939752
1927	13820923
1928	15988120
1929	18478013
1930	20824893
1931	23311119
1932	26241052
1933	29695366
1934	34290117
1935	39695275
1936	46039185
1937	52826802
1938	61906294
1939	73761705
1940	89005424
1941	106009303
1942	124780676
1943	142972663
1944	162191410