Year	metric tons
1961	360800
1962	360320
1963	393748
1964	397300
1965	419300
1966	424450
1967	424174
1968	431700
1969	430000
1970	433000
1971	314678
1972	109952
1973	113102
1974	300236
1975	289186
1976	282106
1977	294271
1978	301519
1979	349887
1980	266238
1981	294042
1982	488520
1983	874586
1984	1443643
1985	2187821
1986	2460924
1987	2929420
1988	3692086
1989	3931967
1990	4136772
1991	4574269
1992	4702572
1993	5042521
1994	4859501
1995	2668863
1996	1931516
1997	2338534
1998	2201566
1999	2454119
2000	2167394
2001	2591615
2002	2852747
2003	2948817
2004	3189319
2005	3006637
2006	3042777
2007	2960073
2008	2431704
2009	1585994
2010	1565155
2011	1414016
2012	1084597
2013	881553
2014	1568940
2015	1616813
2016	1507153
2017	1493955
2018	1378885
2019	1293633
2020	1250955
2021	877638
2022	1068744
