Show data table
| 1970 | 2.9277 Mt | 1989 | 3.6862 Mt | 2008 | 2.8927 Mt |
| 1971 | 2.9579 Mt | 1990 | 3.3705 Mt | 2009 | 2.8105 Mt |
| 1972 | 3.0425 Mt | 1991 | 1.8957 Mt | 2010 | 2.9456 Mt |
| 1973 | 3.0611 Mt | 1992 | 1.6293 Mt | 2011 | 3.369 Mt |
| 1974 | 3.2158 Mt | 1993 | 1.5711 Mt | 2012 | 3.0164 Mt |
| 1975 | 3.1608 Mt | 1994 | 2.484 Mt | 2013 | 3.3303 Mt |
| 1976 | 3.1017 Mt | 1995 | 2.3163 Mt | 2014 | 3.7162 Mt |
| 1977 | 3.211 Mt | 1996 | 2.5608 Mt | 2015 | 3.5927 Mt |
| 1978 | 3.2336 Mt | 1997 | 2.5678 Mt | 2016 | 2.9906 Mt |
| 1979 | 3.5771 Mt | 1998 | 2.5566 Mt | 2017 | 3.2547 Mt |
| 1980 | 3.5404 Mt | 1999 | 2.3625 Mt | 2018 | 4.1619 Mt |
| 1981 | 3.7859 Mt | 2000 | 1.8775 Mt | 2019 | 4.4459 Mt |
| 1982 | 3.045 Mt | 2001 | 1.8252 Mt | 2020 | 4.6314 Mt |
| 1983 | 3.9805 Mt | 2002 | 1.9148 Mt | 2021 | 4.6277 Mt |
| 1984 | 3.8883 Mt | 2003 | 2.3194 Mt | 2022 | 6.2475 Mt |
| 1985 | 3.6328 Mt | 2004 | 2.2153 Mt | 2023 | 6.1404 Mt |
| 1986 | 3.4012 Mt | 2005 | 2.4833 Mt | 2024 | 6.2096 Mt |
| 1987 | 3.7346 Mt | 2006 | 2.5521 Mt | | |
| 1988 | 3.8781 Mt | 2007 | 2.8192 Mt | | |
Show data table
| 1970 | 0.15 t | 1989 | 0.1 t | 2008 | 0.04 t |
| 1971 | 0.14 t | 1990 | 0.09 t | 2009 | 0.04 t |
| 1972 | 0.14 t | 1991 | 0.05 t | 2010 | 0.04 t |
| 1973 | 0.14 t | 1992 | 0.04 t | 2011 | 0.05 t |
| 1974 | 0.14 t | 1993 | 0.04 t | 2012 | 0.04 t |
| 1975 | 0.14 t | 1994 | 0.06 t | 2013 | 0.04 t |
| 1976 | 0.13 t | 1995 | 0.05 t | 2014 | 0.05 t |
| 1977 | 0.13 t | 1996 | 0.06 t | 2015 | 0.04 t |
| 1978 | 0.13 t | 1997 | 0.06 t | 2016 | 0.04 t |
| 1979 | 0.14 t | 1998 | 0.05 t | 2017 | 0.04 t |
| 1980 | 0.13 t | 1999 | 0.05 t | 2018 | 0.05 t |
| 1981 | 0.14 t | 2000 | 0.04 t | 2019 | 0.05 t |
| 1982 | 0.11 t | 2001 | 0.04 t | 2020 | 0.05 t |
| 1983 | 0.14 t | 2002 | 0.04 t | 2021 | 0.05 t |
| 1984 | 0.13 t | 2003 | 0.04 t | 2022 | 0.06 t |
| 1985 | 0.12 t | 2004 | 0.04 t | 2023 | 0.06 t |
| 1986 | 0.11 t | 2005 | 0.04 t | 2024 | 0.06 t |
| 1987 | 0.11 t | 2006 | 0.04 t | | |
| 1988 | 0.11 t | 2007 | 0.05 t | | |