Year	Kilotonnes
1850	0.00012
1851	0.00008
1852	0.00015
1853	0.00014
1854	0.00017
1855	0.00017
1856	0.00023
1857	0.00026
1858	0.00028
1859	0.00026
1860	0.00037
1861	0.00037
1862	0.00041
1863	0.00036
1864	0.00047
1865	0.00046
1866	0.00039
1867	0.00049
1868	0.00047
1869	0.00057
1870	0.00051
1871	0.00046
1872	0.00056
1873	0.0005
1874	0.00056
1875	0.00057
1876	0.00061
1877	0.00054
1878	0.00058
1879	0.00057
1880	0.00051
1881	0.00052
1882	0.00057
1883	0.00042
1884	0.00056
1885	0.00052
1886	0.00048
1887	0.00041
1888	0.0005
1889	0.0004
1890	0.00044
1891	0.00041
1892	0.00047
1893	0.00052
1894	0.00054
1895	0.00055
1896	0.00055
1897	0.00056
1898	0.00067
1899	0.00074
1900	0.0008
1901	0.00105
1902	0.00108
1903	0.00123
1904	0.00129
1905	0.00145
1906	0.00144
1907	0.00156
1908	0.00172
1909	0.00187
1910	0.00191
1911	0.00226
1912	0.00225
1913	0.00202
1914	0.00201
1915	0.00248
1916	0.003
1917	0.00362
1918	0.00402
1919	0.00338
1920	0.00364
1921	0.00301
1922	0.00357
1923	0.00458
1924	0.00456
1925	0.00495
1926	0.00537
1927	0.0059
1928	0.00706
1929	0.00757
1930	0.0066
1931	0.00593
1932	0.00407
1933	0.00491
1934	0.00634
1935	0.00664
1936	0.00677
1937	0.0092
1938	0.00905
1939	0.00893
1940	0.00932
1941	0.01061
1942	0.00987
1943	0.0109
1944	0.0114
1945	0.01199
1946	0.01357
1947	0.01267
1948	0.01316
1949	0.01361
1950	0.01736
1951	0.01924
1952	0.01876
1953	0.01848
1954	0.01808
1955	0.0192
1956	0.02082
1957	0.02135
1958	0.02189
1959	0.02089
1960	0.02072
1961	0.02046
1962	0.02099
1963	0.02152
1964	0.02115
1965	0.02094
1966	0.02063
1967	0.02033
1968	0.01998
1969	0.02012
1970	0.02059
1971	8.521
1972	16.75
1973	31.46
1974	41.44
1975	39.81
1976	36.53
1977	40.41
1978	29.66
1979	40.67
1980	30.23
1981	36.49
1982	19.2
1983	32.99
1984	35.13
1985	35.81
1986	30.51
1987	40.42
1988	36.93
1989	38.21
1990	35.31
1991	40.83
1992	41.12
1993	41.58
1994	44.08
1995	43.8
1996	41.34
1997	44
1998	41.83
1999	32.08
2000	37.82