|
| year | production | consumption |
| 1984 | | |
| 1985 | | |
| 1986 | 1.90 | 4.87 |
| 1987 | 1.98 | 4.24 |
| 1988 | 1.29 | 5.29 |
| 1989 | 1.14 | 2.89 |
| 1990 | 2.58 | 2.40 |
| 1991 | 4.24 | 3.72 |
| 1992 | 2.08 | 2.11 |
| 1993 | 2.39 | 2.38 |
| 1994 | 1.66 | 1.70 |
| 1995 | .32 | .36 |
| 1996 | | .46 |
| 1997 | | .03 |
| 1998 | | .01 |
| 1999 | .27 | 1.23 |
| 2000 | .26 | .46 |
| 2001 | .26 | .20 |
| 2002 | 1.01 | .60 |
| 2003 | | .04 |
| 2004 | | .00 |
| 2005 | | .00 |
| 2006 | .22 | .07 |
| 2007 | .23 | .05 |
| 2008 | .04 | 3.39 |
| 2009 | | 2.22 |
| 2010 | | 3.50 |
|
|
