Year Kilotonnes
1850 0.01162
1851 0.00775
1852 0.01458
1853 0.01313
1854 0.01627
1855 0.01574
1856 0.02165
1857 0.02479
1858 0.0261
1859 0.02465
1860 0.03516
1861 0.03462
1862 0.03868
1863 0.03445
1864 0.04403
1865 0.04349
1866 0.0365
1867 0.04607
1868 0.0446
1869 0.05418
1870 0.0481
1871 0.04387
1872 0.05344
1873 0.04743
1874 0.05339
1875 0.05382
1876 0.0579
1877 0.05093
1878 0.055
1879 0.05355
1880 0.04844
1881 0.04898
1882 0.05391
1883 0.04014
1884 0.05327
1885 0.04922
1886 0.04592
1887 0.039
1888 0.0476
1889 0.03809
1890 0.04165
1891 0.03882
1892 0.04424
1893 0.0492
1894 0.05123
1895 0.05181
1896 0.05252
1897 0.05286
1898 0.06384
1899 0.06977
1900 0.07606
1901 0.0995
1902 0.1024
1903 0.1167
1904 0.1226
1905 0.1369
1906 0.1362
1907 0.1477
1908 0.1627
1909 0.177
1910 0.1809
1911 0.2144
1912 0.2134
1913 0.1918
1914 0.19
1915 0.2346
1916 0.2839
1917 0.3424
1918 0.3811
1919 0.32
1920 0.3446
1921 0.2855
1922 0.3382
1923 0.4336
1924 0.4316
1925 0.4685
1926 0.5085
1927 0.5585
1928 0.6689
1929 0.7173
1930 0.6254
1931 0.5611
1932 0.3855
1933 0.4647
1934 0.6005
1935 0.6286
1936 0.6416
1937 0.8716
1938 0.8571
1939 0.8454
1940 0.8821
1941 1.005
1942 0.9349
1943 1.032
1944 1.079
1945 1.136
1946 1.285
1947 1.2
1948 1.246
1949 1.289
1950 1.644
1951 1.822
1952 1.776
1953 1.75
1954 1.78
1955 1.909
1956 1.979
1957 2.017
1958 1.954
1959 2.002
1960 2.027
1961 1.97
1962 1.95
1963 1.984
1964 2.038
1965 2.105
1966 2.141
1967 2.16
1968 2.207
1969 2.223
1970 2.305
1971 2.252
1972 1.882
1973 2.712
1974 3.148
1975 3.193
1976 2.523
1977 3.156
1978 2.476
1979 3.205
1980 2.255
1981 2.8
1982 2.46
1983 2.196
1984 2.777
1985 2.197
1986 2.079
1987 2.993
1988 2.718
1989 2.672
1990 2.615
1991 2.476
1992 2.345
1993 2.221
1994 2.103
1995 1.991
1996 1.886
1997 1.786
1998 1.691
1999 1.601
2000 1.516