Year Kilotonnes
1850 0.0011
1851 0.00073
1852 0.00138
1853 0.00124
1854 0.00154
1855 0.00149
1856 0.00205
1857 0.00235
1858 0.00247
1859 0.00233
1860 0.00333
1861 0.00328
1862 0.00366
1863 0.00326
1864 0.00417
1865 0.00412
1866 0.00346
1867 0.00436
1868 0.00422
1869 0.00513
1870 0.00456
1871 0.00415
1872 0.00506
1873 0.00449
1874 0.00506
1875 0.0051
1876 0.00548
1877 0.00482
1878 0.00521
1879 0.00507
1880 0.00459
1881 0.00464
1882 0.00511
1883 0.0038
1884 0.00505
1885 0.00466
1886 0.00435
1887 0.00369
1888 0.00451
1889 0.00361
1890 0.00394
1891 0.00368
1892 0.00419
1893 0.00466
1894 0.00485
1895 0.00491
1896 0.00497
1897 0.00501
1898 0.00605
1899 0.00661
1900 0.0072
1901 0.00942
1902 0.0097
1903 0.01106
1904 0.01161
1905 0.01296
1906 0.0129
1907 0.01399
1908 0.01541
1909 0.01676
1910 0.01713
1911 0.02031
1912 0.02021
1913 0.01816
1914 0.01799
1915 0.02222
1916 0.02689
1917 0.03243
1918 0.03609
1919 0.0303
1920 0.03263
1921 0.02704
1922 0.03203
1923 0.04107
1924 0.04088
1925 0.04438
1926 0.04816
1927 0.05289
1928 0.06335
1929 0.06793
1930 0.05923
1931 0.05315
1932 0.03651
1933 0.04402
1934 0.05688
1935 0.05953
1936 0.06076
1937 0.08255
1938 0.08118
1939 0.08007
1940 0.08355
1941 0.09519
1942 0.08855
1943 0.09775
1944 0.1022
1945 0.1076
1946 0.1217
1947 0.1137
1948 0.118
1949 0.122
1950 0.1557
1951 0.1726
1952 0.1682
1953 0.1657
1954 0.2369
1955 0.3063
1956 0.374
1957 0.4399
1958 0.5041
1959 0.5665
1960 0.6272
1961 2.01
1962 1.752
1963 1.909
1964 1.465
1965 2.293
1966 1.892
1967 2.076
1968 6.914
1969 9.942
1970 11.99
1971 11.79
1972 11.11
1973 12.08
1974 12.26
1975 13.5
1976 11.3
1977 12.41
1978 11.46
1979 11.5
1980 12.31
1981 11.33
1982 12
1983 18.29
1984 19.05
1985 20.23
1986 15.74
1987 7.18
1988 10.53
1989 14.48
1990 11.06
1991 12.86
1992 15.58
1993 9.263
1994 10.68
1995 12.63
1996 14.96
1997 19.57
1998 23.02
1999 24.68
2000 36.72