Year	Kilotonnes
1850	0.08845
1851	0.05901
1852	0.111
1853	0.09993
1854	0.1239
1855	0.1198
1856	0.1648
1857	0.1888
1858	0.1987
1859	0.1876
1860	0.2677
1861	0.2636
1862	0.2945
1863	0.2623
1864	0.3352
1865	0.3311
1866	0.2779
1867	0.3508
1868	0.3396
1869	0.4125
1870	0.3662
1871	0.334
1872	0.4069
1873	0.3611
1874	0.4065
1875	0.4098
1876	0.4408
1877	0.3877
1878	0.4188
1879	0.4077
1880	0.3688
1881	0.3729
1882	0.4104
1883	0.3056
1884	0.4055
1885	0.3748
1886	0.3496
1887	0.2969
1888	0.3624
1889	0.29
1890	0.3171
1891	0.2956
1892	0.3368
1893	0.3746
1894	0.3901
1895	0.3945
1896	0.3998
1897	0.4025
1898	0.4861
1899	0.5312
1900	0.5791
1901	0.7576
1902	0.7799
1903	0.8889
1904	0.9336
1905	1.042
1906	1.037
1907	1.125
1908	1.239
1909	1.347
1910	1.377
1911	1.632
1912	1.625
1913	1.46
1914	1.446
1915	1.786
1916	2.162
1917	2.607
1918	2.902
1919	2.436
1920	2.623
1921	2.174
1922	2.575
1923	3.301
1924	3.286
1925	3.567
1926	3.871
1927	4.252
1928	5.093
1929	5.461
1930	4.762
1931	4.272
1932	2.935
1933	3.538
1934	4.572
1935	4.786
1936	4.885
1937	6.636
1938	6.525
1939	6.436
1940	6.716
1941	7.652
1942	7.118
1943	7.858
1944	8.217
1945	8.646
1946	9.781
1947	9.137
1948	9.487
1949	9.811
1950	12.52
1951	13.87
1952	13.52
1953	13.32
1954	13.55
1955	14.53
1956	15.07
1957	15.35
1958	14.87
1959	15.24
1960	15.43
1961	15
1962	14.85
1963	27.6
1964	26.21
1965	27.48
1966	31.25
1967	31.62
1968	33.88
1969	36.58
1970	36.88
1971	37.85
1972	37.05
1973	35.46
1974	37.09
1975	41.95
1976	26.57
1977	28.92
1978	22.47
1979	21.28
1980	20.85
1981	15.67
1982	15.42
1983	13.72
1984	12.2
1985	10.6
1986	10.31
1987	10.96
1988	10.75
1989	9.952
1990	9.649
1991	9.988
1992	15.05
1993	16.12
1994	12.08
1995	13.95
1996	22.52
1997	23.62
1998	27.91
1999	30.36
2000	28.57