Year Kilotonnes 1850 0.00081 1851 0.00081 1852 0.00162 1853 0.00243 1854 0.00324 1855 0.00405 1856 0.00486 1857 0.00568 1858 0.00649 1859 0.0073 1860 0.00812 1861 0.01614 1862 0.02416 1863 0.03218 1864 0.0402 1865 0.04822 1866 0.05624 1867 0.06426 1868 0.07229 1869 0.08031 1870 0.08833 1871 0.09636 1872 0.1047 1873 0.1131 1874 0.1214 1875 0.1298 1876 0.1381 1877 0.1465 1878 0.1549 1879 0.1632 1880 0.1716 1881 0.1943 1882 0.1811 1883 0.1823 1884 0.1835 1885 0.2019 1886 0.2203 1887 0.2387 1888 0.258 1889 0.2868 1890 0.3032 1891 0.2554 1892 0.3295 1893 0.2878 1894 0.3578 1895 0.3159 1896 0.3553 1897 0.4003 1898 0.4139 1899 0.4175 1900 0.4989 1901 0.5434 1902 0.2864 1903 0.3136 1904 0.3724 1905 0.4045 1906 0.3955 1907 0.4283 1908 0.5616 1909 0.5147 1910 0.6142 1911 0.5337 1912 0.6114 1913 0.6988 1914 0.7553 1915 0.8636 1916 0.9498 1917 0.8158 1918 0.8757 1919 0.9581 1920 1.005 1921 1.379 1922 1.422 1923 1.742 1924 1.838 1925 1.821 1926 1.788 1927 1.956 1928 2.029 1929 2.283 1930 2.485 1931 2.048 1932 1.708 1933 2.061 1934 2.487 1935 2.666 1936 2.765 1937 3.522 1938 3.385 1939 3.606 1940 3.352 1941 3.457 1942 3.524 1943 3.535 1944 3.434 1945 3.405 1946 3.299 1947 3.486 1948 4.057 1949 4.199 1950 4.389 1951 5.579 1952 4.201 1953 5.709 1954 2.3 1955 4.1 1956 2.648 1957 3.203 1958 4.353 1959 2.769 1960 0.8583 1961 1.357 1962 0.6847 1963 1.605 1964 6.047 1965 27.26 1966 34.78 1967 37.6 1968 26.96 1969 24.92 1970 32.94 1971 35.84 1972 39.02 1973 42.11 1974 42.02 1975 44.43 1976 53.98 1977 57.81 1978 52.8 1979 48.74 1980 49.91 1981 55.06 1982 59.43 1983 61.6 1984 56.88 1985 50.96 1986 53.75 1987 63.58 1988 64.34 1989 71.94 1990 67.46 1991 69.27 1992 75.47 1993 70.82 1994 65.63 1995 66.21 1996 54.52 1997 54.03 1998 53.71 1999 54.04 2000 55.76