Year	Kilotonnes
1850	0.03255
1851	0.02172
1852	0.04085
1853	0.03677
1854	0.04559
1855	0.0441
1856	0.06065
1857	0.06947
1858	0.07313
1859	0.06906
1860	0.09851
1861	0.09699
1862	0.1084
1863	0.09653
1864	0.1234
1865	0.1218
1866	0.1023
1867	0.1291
1868	0.125
1869	0.1518
1870	0.1348
1871	0.1229
1872	0.1497
1873	0.1329
1874	0.1496
1875	0.1508
1876	0.1622
1877	0.1427
1878	0.1541
1879	0.15
1880	0.1357
1881	0.1372
1882	0.151
1883	0.1125
1884	0.1492
1885	0.1379
1886	0.1287
1887	0.1093
1888	0.1334
1889	0.1067
1890	0.1167
1891	0.1088
1892	0.124
1893	0.1379
1894	0.1435
1895	0.1452
1896	0.1471
1897	0.1481
1898	0.1789
1899	0.1955
1900	0.2131
1901	0.2788
1902	0.5653
1903	0.8588
1904	1.152
1905	1.442
1906	1.692
1907	1.956
1908	2.31
1909	2.609
1910	2.903
1911	3.113
1912	5.806
1913	9.107
1914	10.4
1915	11.34
1916	12.51
1917	15.84
1918	16.92
1919	19.3
1920	22.36
1921	23.49
1922	24.19
1923	23.21
1924	23.23
1925	21.94
1926	20.09
1927	17.08
1928	40.08
1929	48.72
1930	60.09
1931	49.43
1932	47.58
1933	49.9
1934	55.34
1935	62.71
1936	67.86
1937	81.88
1938	82.89
1939	81.01
1940	67.6
1941	86.7
1942	47.94
1943	78.33
1944	103.3
1945	123.4
1946	135.7
1947	154
1948	162.1
1949	172.3
1950	185.1
1951	204.3
1952	191.1
1953	172.5
1954	175.7
1955	170.6
1956	159.5
1957	133.8
1958	113.8
1959	115.2
1960	107.9
1961	103.4
1962	98.96
1963	92.14
1964	87.81
1965	80
1966	73.05
1967	76.89
1968	71.58
1969	69.21
1970	76.21
1971	61.59
1972	56.82
1973	64.5
1974	65.1
1975	38.97
1976	48.63
1977	42.25
1978	40.74
1979	36.72
1980	50.17
1981	40.6
1982	33.3
1983	26.03
1984	22.96
1985	10.04
1986	9.378
1987	11.38
1988	12.1
1989	12.29
1990	13.23
1991	13.43
1992	13.61
1993	13.75
1994	13.9
1995	14.06
1996	14.22
1997	14.39
1998	14.58
1999	14.78
2000	15
