|
| year | production | consumption |
| 1984 | | |
| 1985 | | |
| 1986 | 2.47 | 2.28 |
| 1987 | 2.18 | 2.20 |
| 1988 | 2.18 | 2.01 |
| 1989 | 2.18 | 2.01 |
| 1990 | 2.55 | 2.38 |
| 1991 | 2.44 | 2.29 |
| 1992 | 2.47 | 2.18 |
| 1993 | 2.50 | 2.22 |
| 1994 | 3.07 | 2.92 |
| 1995 | 4.34 | 3.20 |
| 1996 | 4.03 | 3.50 |
| 1997 | 5.23 | 3.25 |
| 1998 | 5.25 | 3.19 |
| 1999 | 4.85 | 3.37 |
| 2000 | 5.28 | 4.10 |
| 2001 | 5.57 | 3.52 |
| 2002 | 2.96 | 2.88 |
| 2003 | 4.60 | 3.05 |
| 2004 | 5.45 | 2.77 |
| 2005 | 7.45 | 3.07 |
| 2006 | 6.35 | 2.52 |
| 2007 | 5.46 | 3.18 |
| 2008 | 5.53 | 1.84 |
| 2009 | | |
| 2010 | | |
|
|
