|
| year | production | consumption |
| 1984 | | |
| 1985 | | |
| 1986 | 1.36 | 2.87 |
| 1987 | 1.29 | 2.69 |
| 1988 | 1.33 | 2.65 |
| 1989 | 1.69 | 3.16 |
| 1990 | 1.63 | 3.12 |
| 1991 | 1.47 | 3.21 |
| 1992 | 1.58 | 3.57 |
| 1993 | | 4.40 |
| 1994 | | 5.07 |
| 1995 | | 4.65 |
| 1996 | | 5.91 |
| 1997 | | 5.92 |
| 1998 | | 6.68 |
| 1999 | | 7.10 |
| 2000 | | 7.11 |
| 2001 | | 7.60 |
| 2002 | | 7.60 |
| 2003 | | 7.45 |
| 2004 | | 7.02 |
| 2005 | | 7.08 |
| 2006 | | 7.90 |
| 2007 | | 9.53 |
| 2008 | | 9.39 |
| 2009 | | 10.68 |
| 2010 | | 11.12 |
|
|