Year metric tons 1960 1716905 1961 1809529 1962 1947150 1963 2005689 1964 2177282 1965 2309351 1966 2438117 1967 2542377 1968 2680180 1969 2826341 1970 3017057 1971 3281124 1972 3533724 1973 3623206 1974 3606395 1975 3507636 1976 3576881 1977 3725548 1978 3786435 1979 3760546 1980 3752152 1981 3877846 1982 3922317 1983 4142377.24 1984 4253046.140000001 1985 4357009.11 1986 4652480.72 1987 4800328.28 1988 4880818.970000001 1989 5000169.99 1990 5228203.170000001 1991 5256803.25 1992 5501168 1993 5552831.610000001 1994 5487292.279999999 1995 5779819.73 1996 5823481.16 1997 6225979.42 1998 6434171.089999999 1999 7107098.609999999 2000 7348775.739999999 2001 7605271.07 2002 7761059.8 2003 8242053.279999999 2004 8960300.700000001 2005 9268321.020000001 2006 9500514.85 2007 9579756.040000001 2008 9647361.85 2009 10132007.02 2010 10334765.290000001 2011 10595796.250000002 2012 10891962.63 2013 11034272.509999998 2014 11395947.770000001 2015 11326757.640000002 2016 11928551.299999999 2017 12959360.819999998 2018 13117648.51 2019 12966058.56 2020 12567995.43 2021 12612899.100000001 2022 12616669.85