|
| year | production | consumption |
| 1980 | | 23.15 |
| 1981 | | 19.84 |
| 1982 | | 25.35 |
| 1983 | | 19.84 |
| 1984 | | 24.25 |
| 1985 | | 17.64 |
| 1986 | | 16.53 |
| 1987 | | 5.51 |
| 1988 | | 8.82 |
| 1989 | | 17.64 |
| 1990 | | 26.46 |
| 1991 | | 19.84 |
| 1992 | | 22.05 |
| 1993 | | 22.05 |
| 1994 | | 22.05 |
| 1995 | | 22.05 |
| 1996 | | 24.25 |
| 1997 | | 24.25 |
| 1998 | | 22.05 |
| 1999 | | 19.84 |
| 2000 | | 18.74 |
| 2001 | | 16.53 |
| 2002 | | 17.97 |
| 2003 | | 18.19 |
| 2004 | | .22 |
| 2005 | | |
| 2006 | | |
| 2007 | | |
| 2008 | | |
| 2009 | | |
| 2010 | | |
| 2011 | | |
|
|