|
| year | production | consumption |
| 1984 | .26 | .16 |
| 1985 | .26 | .16 |
| 1986 | .26 | .16 |
| 1987 | | .07 |
| 1988 | | .20 |
| 1989 | | .16 |
| 1990 | | .07 |
| 1991 | | .10 |
| 1992 | .26 | .16 |
| 1993 | .26 | .26 |
| 1994 | .18 | .14 |
| 1995 | .79 | .92 |
| 1996 | .17 | .70 |
| 1997 | .26 | 1.57 |
| 1998 | .26 | 1.28 |
| 1999 | .13 | 1.15 |
| 2000 | .04 | 1.04 |
| 2001 | .07 | .41 |
| 2002 | .22 | .26 |
| 2003 | .22 | .15 |
| 2004 | .81 | .01 |
| 2005 | .37 | .02 |
| 2006 | | .03 |
| 2007 | | -.01 |
| 2008 | .02 | .02 |
| 2009 | | .03 |
| 2010 | | .03 |
|
|