Year	metric tons
1960	3500
1961	4000
1962	4300
1963	4500
1964	5000
1965	6000
1966	7300
1967	7500
1968	10000
1969	10000
1970	9111
1971	10921
1972	10942
1973	11333
1974	11150
1975	14420
1976	12820
1977	10847
1978	15363
1979	8096
1980	9134
1981	10325
1982	14530
1983	14878
1984	14675
1985	15544
1986	14824
1987	15175
1988	15455
1989	16444
1990	15778
1991	12502
1992	10749
1993	16964
1994	13052
1995	12201
1996	15098
1997	14290
1998	16677
1999	22924
2000	22277
2001	23163
2002	20946
2003	27485
2004	28013
2005	27706
2006	24830
2007	19905
2008	22765
2009	27025
2010	27535
2011	24122
2012	19320
2013	20015
2014	19849
2015	21497
2016	31891
2017	26915
2018	24620
2019	25526
2020	18034
2021	17984
2022	21505.22