|
| year | production | consumption |
| 1984 | | |
| 1985 | | |
| 1986 | 1.33 | 1.49 |
| 1987 | 1.23 | 1.30 |
| 1988 | 1.26 | 1.36 |
| 1989 | 2.10 | 2.10 |
| 1990 | 2.04 | 1.46 |
| 1991 | 2.04 | 1.48 |
| 1992 | 2.09 | 1.58 |
| 1993 | 2.04 | 1.24 |
| 1994 | 2.22 | 1.29 |
| 1995 | .77 | .98 |
| 1996 | .82 | 1.44 |
| 1997 | 1.66 | 1.41 |
| 1998 | 1.40 | 1.05 |
| 1999 | 1.47 | 1.08 |
| 2000 | 1.47 | .82 |
| 2001 | 1.26 | 1.12 |
| 2002 | 1.50 | 1.05 |
| 2003 | 1.61 | 1.00 |
| 2004 | 1.58 | 1.03 |
| 2005 | 1.71 | 1.05 |
| 2006 | 1.43 | .84 |
| 2007 | 1.31 | .84 |
| 2008 | 1.64 | 1.05 |
| 2009 | 1.33 | .77 |
| 2010 | 2.24 | 1.33 |
|
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