|
| year | production | consumption |
| 1984 | | |
| 1985 | | |
| 1986 | 6.20 | 10.45 |
| 1987 | 7.21 | 11.04 |
| 1988 | 7.65 | 11.29 |
| 1989 | 7.91 | 12.92 |
| 1990 | 9.25 | 13.11 |
| 1991 | 11.64 | 11.64 |
| 1992 | 26.39 | 21.50 |
| 1993 | 17.53 | 21.73 |
| 1994 | 16.36 | 21.73 |
| 1995 | 23.14 | 21.79 |
| 1996 | 20.56 | 20.98 |
| 1997 | 24.66 | 22.34 |
| 1998 | 24.12 | 24.12 |
| 1999 | 19.16 | 19.16 |
| 2000 | 25.19 | 22.00 |
| 2001 | 17.00 | 25.54 |
| 2002 | 22.60 | 23.67 |
| 2003 | 24.75 | 26.99 |
| 2004 | 26.52 | 27.99 |
| 2005 | 27.93 | 29.17 |
| 2006 | 27.76 | 33.04 |
| 2007 | 26.34 | 32.39 |
| 2008 | 27.23 | 33.12 |
| 2009 | 24.63 | 35.76 |
| 2010 | 19.33 | 26.95 |
|
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