|
| year | production | consumption |
| 1984 | | |
| 1985 | | |
| 1986 | 11.95 | 7.10 |
| 1987 | 9.48 | 6.32 |
| 1988 | 12.19 | 8.50 |
| 1989 | 12.23 | 12.22 |
| 1990 | 12.46 | 12.46 |
| 1991 | 12.57 | 9.39 |
| 1992 | 11.47 | 9.92 |
| 1993 | 9.83 | 8.17 |
| 1994 | 15.70 | 3.58 |
| 1995 | 15.15 | 3.21 |
| 1996 | 14.39 | 14.97 |
| 1997 | 13.31 | 15.17 |
| 1998 | 16.53 | 16.30 |
| 1999 | 17.26 | 16.16 |
| 2000 | 17.40 | 16.91 |
| 2001 | 21.02 | 19.68 |
| 2002 | 18.24 | 18.95 |
| 2003 | 18.09 | 18.03 |
| 2004 | 17.60 | 18.17 |
| 2005 | 14.61 | 19.10 |
| 2006 | 16.86 | 21.62 |
| 2007 | 13.28 | 26.73 |
| 2008 | 22.28 | 33.68 |
| 2009 | 36.69 | 30.91 |
| 2010 | 30.45 | 26.50 |
|
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