Year Kilotonnes
1850 0
1851 0.00229
1852 0.00458
1853 0.00687
1854 0.00916
1855 0.01145
1856 0.01374
1857 0.01603
1858 0.01832
1859 0.02061
1860 0.0229
1861 0.02509
1862 0.02725
1863 0.02939
1864 0.03152
1865 0.03362
1866 0.03571
1867 0.03777
1868 0.03982
1869 0.04184
1870 0.04385
1871 0.04986
1872 0.05589
1873 0.0619
1874 0.0679
1875 0.0821
1876 0.08963
1877 0.09612
1878 0.1065
1879 0.1164
1880 0.1221
1881 0.1269
1882 0.1339
1883 0.1443
1884 0.1604
1885 0.1768
1886 0.177
1887 0.1932
1888 0.2119
1889 0.2378
1890 0.2549
1891 0.2789
1892 0.296
1893 0.2883
1894 0.329
1895 0.3578
1896 0.3786
1897 0.3905
1898 0.4483
1899 0.4774
1900 0.5276
1901 0.5931
1902 0.6458
1903 0.6799
1904 0.7149
1905 0.7614
1906 1.043
1907 1.115
1908 1.193
1909 1.203
1910 1.248
1911 1.335
1912 1.509
1913 1.708
1914 1.783
1915 1.769
1916 2.026
1917 2.203
1918 2.269
1919 2.532
1920 2.006
1921 2.133
1922 2.203
1923 2.39
1924 2.528
1925 2.561
1926 2.577
1927 2.259
1928 2.193
1929 1.894
1930 1.59
1931 0.81
1932 0.5
1933 0.5
1934 0.5
1935 0.5
1936 0.52
1937 0.5
1938 0.52
1939 0.59
1940 0.69
1941 0.76
1942 0.62
1943 0.49
1944 0.14
1945 0.04
1946 1.229
1947 2.418
1948 3.607
1949 4.795
1950 5.984
1951 6.248
1952 9.468
1953 8.16
1954 7.745
1955 7.542
1956 7.339
1957 7.135
1958 6.932
1959 6.729
1960 6.526
1961 6.323
1962 6.12
1963 5.917
1964 5.714
1965 5.511
1966 5.308
1967 5.105
1968 4.902
1969 4.699
1970 4.496
1971 4.293
1972 4.09
1973 3.887
1974 3.684
1975 3.481
1976 3.277
1977 3.074
1978 2.871
1979 2.668
1980 2.465
1981 2.262
1982 2.059
1983 1.856
1984 1.653
1985 1.45
1986 1.5
1987 1.55
1988 1.55
1989 1.65
1990 1.7
1991 1.75
1992 1.85
1993 1.85
1994 2
1995 2.3
1996 2.55
1997 2.8
1998 3.098
1999 3.5
2000 3.92