|
| year | production | consumption |
| 1980 | | 20.00 |
| 1981 | | 15.19 |
| 1982 | | 11.00 |
| 1983 | | 10.45 |
| 1984 | | 11.00 |
| 1985 | | 12.00 |
| 1986 | | 12.00 |
| 1987 | | 14.00 |
| 1988 | | 15.00 |
| 1989 | | 17.00 |
| 1990 | | 17.00 |
| 1991 | | 18.00 |
| 1992 | | 18.79 |
| 1993 | | 19.53 |
| 1994 | | 19.67 |
| 1995 | | 22.46 |
| 1996 | | 24.54 |
| 1997 | | 25.00 |
| 1998 | | 25.18 |
| 1999 | | 26.03 |
| 2000 | | 26.66 |
| 2001 | | 27.69 |
| 2002 | | 42.06 |
| 2003 | | 42.55 |
| 2004 | | 48.06 |
| 2005 | | 47.29 |
| 2006 | | 49.55 |
| 2007 | | 46.33 |
| 2008 | | 44.32 |
| 2009 | | 44.81 |
| 2010 | | 48.17 |
| 2011 | | 41.78 |
|
|