Year	Kilotonnes
1850	0.04609
1851	0.03696
1852	0.04626
1853	0.0187
1854	0.00957
1855	0.00966
1856	0.0374
1857	0.03748
1858	0.03757
1859	0.03766
1860	0.04696
1861	0.04705
1862	0.05635
1863	0.06565
1864	0.08416
1865	0.07503
1866	0.112
1867	0.149
1868	0.1583
1869	0.1584
1870	0.0848
1871	0.1034
1872	0.1128
1873	0.1129
1874	0.1038
1875	0.104
1876	0.104
1877	0.1132
1878	0.08552
1879	0.09053
1880	0.09555
1881	0.1707
1882	0.1922
1883	0.2271
1884	0.272
1885	0.2479
1886	0.2251
1887	0.2182
1888	0.2515
1889	0.2851
1890	0.2885
1891	0.3428
1892	0.3161
1893	0.3398
1894	0.3639
1895	0.3886
1896	0.4268
1897	0.4943
1898	0.5508
1899	0.6332
1900	0.6668
1901	0.7135
1902	0.6833
1903	0.7194
1904	0.7705
1905	0.8562
1906	0.902
1907	1.061
1908	1.07
1909	1.009
1910	1.172
1911	1.226
1912	1.306
1913	1.306
1914	1.202
1915	1.072
1916	1.008
1917	0.9969
1918	1.024
1919	0.7068
1920	0.8585
1921	0.8045
1922	0.8709
1923	0.9775
1924	0.9759
1925	0.9793
1926	0.9628
1927	1.037
1928	0.9977
1929	0.9845
1930	0.9532
1931	0.8193
1932	0.8907
1933	0.9046
1934	0.9332
1935	0.9909
1936	1.073
1937	1.187
1938	1.224
1939	1.293
1940	1.289
1941	1.382
1942	1.381
1943	1.325
1944	1.327
1945	1.245
1946	1.271
1947	1.293
1948	1.335
1949	1.356
1950	1.465
1951	1.483
1952	1.612
1953	1.698
1954	1.91
1955	2.197
1956	2.476
1957	2.544
1958	2.706
1959	2.83
1960	3.052
1961	2.964
1962	3.084
1963	3.289
1964	3.283
1965	3.333
1966	3.502
1967	3.562
1968	3.673
1969	3.749
1970	3.79
1971	7.468
1972	8.891
1973	8.788
1974	7.664
1975	6.889
1976	8.281
1977	8.933
1978	8.561
1979	9.009
1980	9.931
1981	9.333
1982	8.558
1983	6.61
1984	5.692
1985	4.774
1986	3.856
1987	2.938
1988	2.02
1989	1.102
1990	0.1844
1991	0.188
1992	0.1916
1993	0.1954
1994	0.1992
1995	0.203
1996	0.207
1997	0.211
1998	0.2151
1999	0.2193
2000	0.2235