Year Kilotonnes
1850 0.04707
1851 0.0314
1852 0.05907
1853 0.05317
1854 0.06592
1855 0.06376
1856 0.0877
1857 0.1005
1858 0.1057
1859 0.09985
1860 0.1424
1861 0.1402
1862 0.1567
1863 0.1396
1864 0.1784
1865 0.1762
1866 0.1479
1867 0.1867
1868 0.1807
1869 0.2195
1870 0.1949
1871 0.1777
1872 0.2165
1873 0.1922
1874 0.2163
1875 0.218
1876 0.2346
1877 0.2063
1878 0.2228
1879 0.217
1880 0.1962
1881 0.1984
1882 0.2184
1883 0.1626
1884 0.2158
1885 0.1994
1886 0.186
1887 0.158
1888 0.1928
1889 0.1543
1890 0.1687
1891 0.1573
1892 0.1792
1893 0.1993
1894 0.2076
1895 0.2099
1896 0.2128
1897 0.2142
1898 0.2586
1899 0.2827
1900 0.3081
1901 0.4031
1902 0.415
1903 0.473
1904 0.4968
1905 0.5545
1906 0.5518
1907 0.5985
1908 0.6591
1909 0.717
1910 0.7328
1911 0.8686
1912 0.8645
1913 0.7769
1914 0.7697
1915 0.9503
1916 1.15
1917 1.387
1918 1.544
1919 1.296
1920 1.396
1921 1.157
1922 1.37
1923 1.757
1924 1.749
1925 1.898
1926 2.06
1927 2.263
1928 2.71
1929 2.906
1930 2.534
1931 2.273
1932 1.562
1933 1.883
1934 2.433
1935 2.547
1936 2.599
1937 3.531
1938 3.472
1939 3.425
1940 3.574
1941 4.072
1942 3.788
1943 4.181
1944 4.372
1945 4.601
1946 5.205
1947 4.862
1948 5.048
1949 5.22
1950 6.66
1951 7.381
1952 7.196
1953 7.09
1954 7.211
1955 7.733
1956 8.017
1957 8.17
1958 7.915
1959 8.11
1960 8.21
1961 7.982
1962 7.901
1963 8.036
1964 9.55
1965 7.779
1966 8.67
1967 8.683
1968 8.693
1969 5.648
1970 2.892
1971 7.117
1972 6.472
1973 9.237
1974 9.888
1975 10.28
1976 10.88
1977 12.2
1978 12.05
1979 10.95
1980 11.81
1981 9.983
1982 7.738
1983 7.614
1984 7.385
1985 7.709
1986 8.043
1987 8.929
1988 8.311
1989 7.796
1990 8.003
1991 9.77
1992 11.66
1993 13.61
1994 13.85
1995 13.91
1996 15.37
1997 17.33
1998 21.34
1999 25.46
2000 27.44