Year	metric tons
1960	63700
1961	61600
1962	59900
1963	62000
1964	59500
1965	59700
1966	62800
1967	63800
1968	68200
1969	58700
1970	53000
1971	60200
1972	59000
1973	53300
1974	46820
1975	49031
1976	44503
1977	45372
1978	50597
1979	47157
1980	45705
1981	49426
1982	48044
1983	48835
1984	48181
1985	45555
1986	39996
1987	40831
1988	42241
1989	40368
1990	42135
1991	40737
1992	37966
1993	36935
1994	35100
1995	36445
1996	31769
1997	31346
1998	31681
1999	31473
2000	31671
2001	32039
2002	30862
2003	28092
2004	27474
2005	24981
2006	23147
2007	24669
2008	22735
2009	22298
2010	22957
2011	22578
2012	24936
2013	25874
2014	27007
2015	24803
2016	27014
2017	24724
2018	23116
2019	21436
2020	20162.8
2021	18160
2022	18953