|
| year | production | consumption |
| 1984 | | |
| 1985 | | |
| 1986 | 6.90 | 6.87 |
| 1987 | 7.22 | 7.20 |
| 1988 | 7.22 | 7.20 |
| 1989 | 7.22 | 7.20 |
| 1990 | 8.45 | |
| 1991 | 6.04 | 8.00 |
| 1992 | 5.13 | 7.32 |
| 1993 | 5.38 | 5.35 |
| 1994 | 6.92 | 6.87 |
| 1995 | 6.65 | 7.25 |
| 1996 | 6.06 | 6.50 |
| 1997 | 7.08 | 6.49 |
| 1998 | 7.10 | 6.46 |
| 1999 | 7.24 | 5.54 |
| 2000 | 7.53 | 6.08 |
| 2001 | 7.74 | 6.50 |
| 2002 | 5.42 | 5.52 |
| 2003 | 6.78 | 5.73 |
| 2004 | 9.37 | 6.60 |
| 2005 | 9.18 | 6.85 |
| 2006 | 8.27 | 6.73 |
| 2007 | 9.11 | 9.02 |
| 2008 | 9.32 | 8.79 |
| 2009 | 8.18 | 9.49 |
| 2010 | 8.95 | 8.02 |
|
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