|
| year | production | consumption |
| 1984 | | |
| 1985 | | |
| 1986 | 20.69 | 16.49 |
| 1987 | 20.67 | 15.90 |
| 1988 | 7.54 | 21.54 |
| 1989 | 10.59 | 28.99 |
| 1990 | 11.00 | 30.00 |
| 1991 | 5.77 | 9.87 |
| 1992 | 13.18 | 11.59 |
| 1993 | 19.67 | 17.45 |
| 1994 | 19.75 | 6.08 |
| 1995 | 19.77 | 19.77 |
| 1996 | 19.68 | 17.14 |
| 1997 | 32.51 | 37.47 |
| 1998 | 33.20 | 30.82 |
| 1999 | 32.08 | 29.22 |
| 2000 | 32.55 | 21.67 |
| 2001 | 35.23 | 40.62 |
| 2002 | 38.11 | 24.76 |
| 2003 | 33.40 | 25.29 |
| 2004 | 4.18 | 20.95 |
| 2005 | 36.61 | 29.47 |
| 2006 | 33.40 | 50.28 |
| 2007 | 3.85 | 48.15 |
| 2008 | 5.12 | 48.62 |
| 2009 | 5.48 | 19.27 |
| 2010 | 44.55 | 47.57 |
|
|
