Year Kilotonnes
1850 0.00757
1851 0.00505
1852 0.0095
1853 0.00855
1854 0.0106
1855 0.01026
1856 0.01411
1857 0.01616
1858 0.01701
1859 0.01606
1860 0.02291
1861 0.02256
1862 0.02521
1863 0.02245
1864 0.0287
1865 0.02834
1866 0.02378
1867 0.03003
1868 0.02907
1869 0.03531
1870 0.03135
1871 0.02859
1872 0.03482
1873 0.03091
1874 0.03479
1875 0.03507
1876 0.03773
1877 0.03319
1878 0.03584
1879 0.0349
1880 0.03157
1881 0.03192
1882 0.03513
1883 0.02616
1884 0.03471
1885 0.03208
1886 0.02992
1887 0.02542
1888 0.03102
1889 0.02482
1890 0.02714
1891 0.0253
1892 0.02883
1893 0.03206
1894 0.03339
1895 0.03376
1896 0.03422
1897 0.03445
1898 0.04161
1899 0.04547
1900 0.04956
1901 0.06484
1902 0.06675
1903 0.07608
1904 0.07991
1905 0.0892
1906 0.08875
1907 0.09628
1908 0.106
1909 0.1153
1910 0.1179
1911 0.1397
1912 0.1391
1913 0.125
1914 0.1238
1915 0.1529
1916 0.185
1917 0.2231
1918 0.2484
1919 0.2085
1920 0.2245
1921 0.1861
1922 0.2204
1923 0.2826
1924 0.2813
1925 0.3053
1926 0.3314
1927 0.3639
1928 0.4359
1929 0.4674
1930 0.4076
1931 0.3657
1932 0.2512
1933 0.3029
1934 0.3914
1935 0.4096
1936 0.4181
1937 0.568
1938 0.5585
1939 0.5509
1940 0.5749
1941 0.655
1942 0.6093
1943 0.6726
1944 0.7033
1945 0.7401
1946 0.8372
1947 0.782
1948 0.812
1949 0.8397
1950 1.071
1951 1.187
1952 1.158
1953 1.14
1954 1.16
1955 1.244
1956 1.29
1957 1.314
1958 1.273
1959 1.305
1960 1.321
1961 1.284
1962 1.271
1963 1.293
1964 1.328
1965 1.372
1966 1.395
1967 4.168
1968 5.242
1969 4.523
1970 5.673
1971 4.927
1972 5.62
1973 6.796
1974 7.092
1975 6.221
1976 6.402
1977 6.926
1978 9.288
1979 8.458
1980 8.389
1981 7.926
1982 6.037
1983 4.29
1984 4.319
1985 3.566
1986 4.661
1987 6.797
1988 7.253
1989 8.347
1990 8.068
1991 8.365
1992 8.489
1993 8.315
1994 9.14
1995 9.854
1996 10.7
1997 11.62
1998 11.11
1999 10.44
2000 10.81