|
| year | production | consumption |
| 1984 | | |
| 1985 | | |
| 1986 | | 2.23 |
| 1987 | 4.09 | 2.40 |
| 1988 | 3.94 | 2.00 |
| 1989 | 2.86 | 4.42 |
| 1990 | 3.32 | 3.39 |
| 1991 | 3.33 | 3.39 |
| 1992 | 3.10 | 3.82 |
| 1993 | 3.03 | 3.74 |
| 1994 | 3.07 | 3.81 |
| 1995 | 3.01 | 3.74 |
| 1996 | 3.02 | 3.75 |
| 1997 | 3.03 | 3.76 |
| 1998 | 3.05 | 3.79 |
| 1999 | 3.05 | 3.79 |
| 2000 | 3.08 | 3.88 |
| 2001 | | 3.90 |
| 2002 | | 3.82 |
| 2003 | | 4.03 |
| 2004 | | .90 |
| 2005 | | 3.99 |
| 2006 | | 7.95 |
| 2007 | | 7.87 |
| 2008 | | 8.03 |
| 2009 | | 8.05 |
| 2010 | | 8.05 |
|
|
