Year metric tons 1960 0 1961 0 1962 0 1963 0 1964 0 1965 0 1966 0 1967 0 1968 0 1969 10 1970 19 1971 27 1972 50 1973 93 1974 158 1975 286 1976 433 1977 780 1978 1132 1979 1687 1980 3737 1981 5794 1982 7586 1983 9168 1984 10700 1985 10873 1986 10990 1987 13140 1988 15559 1989 18170 1990 20490 1991 23390 1992 29820 1993 30390 1994 30915 1995 46202 1996 77690 1997 87676 1998 103915 1999 140657 2000 172450 2001 205568 2002 247678 2003 273268 2004 269699 2005 257784 2006 271697 2007 289048 2008 331553 2009 365127 2010 411777 2011 436084 2012 480880 2013 477634.46 2014 564221.57 2015 578372.92 2016 542982.01 2017 565196.44 2018 581637.72 2019 600600.1 2020 630800.2 2021 650572.21 2022 738881