Show data table
| 1970 | 0.0416 Mt | 1989 | 0.0772 Mt | 2008 | 6.6067 Mt |
| 1971 | 0.0416 Mt | 1990 | 0.0711 Mt | 2009 | 5.4778 Mt |
| 1972 | 0.0479 Mt | 1991 | 0.0741 Mt | 2010 | 5.7159 Mt |
| 1973 | 0.0289 Mt | 1992 | 0.0741 Mt | 2011 | 5.9609 Mt |
| 1974 | 0.0352 Mt | 1993 | 0.0772 Mt | 2012 | 5.61 Mt |
| 1975 | 0.0382 Mt | 1994 | 1.2117 Mt | 2013 | 5.7233 Mt |
| 1976 | 0.0383 Mt | 1995 | 1.2873 Mt | 2014 | 5.7179 Mt |
| 1977 | 0.0383 Mt | 1996 | 1.4079 Mt | 2015 | 5.4069 Mt |
| 1978 | 0.0734 Mt | 1997 | 1.9362 Mt | 2016 | 5.3893 Mt |
| 1979 | 0.0704 Mt | 1998 | 2.3542 Mt | 2017 | 4.887 Mt |
| 1980 | 0.0642 Mt | 1999 | 2.5728 Mt | 2018 | 5.3152 Mt |
| 1981 | 0.0832 Mt | 2000 | 2.7446 Mt | 2019 | 5.1224 Mt |
| 1982 | 0.064 Mt | 2001 | 3.6006 Mt | 2020 | 4.9101 Mt |
| 1983 | 0.0419 Mt | 2002 | 3.2122 Mt | 2021 | 5.0308 Mt |
| 1984 | 0.045 Mt | 2003 | 3.5906 Mt | 2022 | 5.0888 Mt |
| 1985 | 0.0422 Mt | 2004 | 6.2799 Mt | 2023 | 4.7651 Mt |
| 1986 | 0.0484 Mt | 2005 | 6.3957 Mt | 2024 | 4.8269 Mt |
| 1987 | 0.0515 Mt | 2006 | 6.3863 Mt | | |
| 1988 | 0.0579 Mt | 2007 | 7.1364 Mt | | |
Show data table
| 1970 | 0.13 t | 1989 | 0.17 t | 2008 | 6.09 t |
| 1971 | 0.13 t | 1990 | 0.15 t | 2009 | 4.82 t |
| 1972 | 0.15 t | 1991 | 0.15 t | 2010 | 4.81 t |
| 1973 | 0.1 t | 1992 | 0.15 t | 2011 | 4.8 t |
| 1974 | 0.12 t | 1993 | 0.15 t | 2012 | 4.34 t |
| 1975 | 0.13 t | 1994 | 2.2 t | 2013 | 4.25 t |
| 1976 | 0.14 t | 1995 | 2.25 t | 2014 | 4.08 t |
| 1977 | 0.14 t | 1996 | 2.37 t | 2015 | 3.72 t |
| 1978 | 0.27 t | 1997 | 3.14 t | 2016 | 3.57 t |
| 1979 | 0.25 t | 1998 | 3.67 t | 2017 | 3.13 t |
| 1980 | 0.22 t | 1999 | 3.86 t | 2018 | 3.29 t |
| 1981 | 0.27 t | 2000 | 3.9 t | 2019 | 3.07 t |
| 1982 | 0.2 t | 2001 | 4.8 t | 2020 | 2.86 t |
| 1983 | 0.12 t | 2002 | 4.03 t | 2021 | 2.86 t |
| 1984 | 0.12 t | 2003 | 4.23 t | 2022 | 2.82 t |
| 1985 | 0.11 t | 2004 | 6.98 t | 2023 | 2.58 t |
| 1986 | 0.12 t | 2005 | 6.75 t | 2024 | 2.55 t |
| 1987 | 0.12 t | 2006 | 6.45 t | | |
| 1988 | 0.13 t | 2007 | 6.89 t | | |