Year Kilotonnes
1850 0
1851 0.0043
1852 0.0086
1853 0.0129
1854 0.0172
1855 0.0215
1856 0.02579
1857 0.03009
1858 0.03439
1859 0.03869
1860 0.04299
1861 0.04709
1862 0.05115
1863 0.05517
1864 0.05916
1865 0.0631
1866 0.06702
1867 0.07089
1868 0.07473
1869 0.07853
1870 0.0823
1871 0.09358
1872 0.1049
1873 0.1162
1874 0.1274
1875 0.1541
1876 0.1682
1877 0.1804
1878 0.2
1879 0.2185
1880 0.2291
1881 0.2381
1882 0.2512
1883 0.2709
1884 0.3011
1885 0.3318
1886 0.3322
1887 0.3627
1888 0.3976
1889 0.4463
1890 0.4784
1891 0.5235
1892 0.5556
1893 0.541
1894 0.6175
1895 0.6715
1896 0.7105
1897 0.733
1898 0.8414
1899 0.8961
1900 0.9903
1901 1.113
1902 1.212
1903 1.276
1904 1.342
1905 1.429
1906 1.957
1907 2.092
1908 2.239
1909 2.259
1910 2.342
1911 2.507
1912 2.832
1913 3.205
1914 3.346
1915 3.319
1916 3.803
1917 4.135
1918 4.259
1919 4.753
1920 3.766
1921 4.003
1922 4.135
1923 4.485
1924 4.746
1925 4.807
1926 4.838
1927 5.095
1928 5.221
1929 5.359
1930 5.355
1931 5.051
1932 4.893
1933 5.214
1934 5.741
1935 6.103
1936 6.49
1937 6.696
1938 6.766
1939 7.315
1940 8.241
1941 8.748
1942 8.746
1943 8.363
1944 8.186
1945 5.086
1946 4.16
1947 4.7
1948 4.919
1949 6.486
1950 7.438
1951 5.393
1952 8.244
1953 7.991
1954 5.809
1955 3.991
1956 3.379
1957 6.674
1958 3.883
1959 3.727
1960 5.46
1961 2.884
1962 2.953
1963 3.163
1964 3.753
1965 2.951
1966 0.6482
1967 2.845
1968 1.241
1969 6.07
1970 17.63
1971 14.32
1972 15.86
1973 15.51
1974 14.81
1975 13.86
1976 12.59
1977 14.54
1978 13.72
1979 13.26
1980 18.86
1981 14.98
1982 17.18
1983 11.66
1984 13.05
1985 11.75
1986 10.9
1987 15
1988 13.7
1989 13.3
1990 13
1991 14.8
1992 22.3
1993 20.95
1994 20.4
1995 19
1996 32.3
1997 30.7
1998 31.27
1999 26.49
2000 27.84