|
| year | production | consumption |
| 1984 | | |
| 1985 | | |
| 1986 | .11 | .11 |
| 1987 | .08 | .08 |
| 1988 | .08 | .08 |
| 1989 | .07 | .07 |
| 1990 | .07 | .07 |
| 1991 | .08 | .08 |
| 1992 | .08 | .08 |
| 1993 | .06 | .06 |
| 1994 | .08 | .08 |
| 1995 | .06 | .05 |
| 1996 | .05 | .05 |
| 1997 | | .59 |
| 1998 | | .04 |
| 1999 | | .04 |
| 2000 | | .05 |
| 2001 | | .05 |
| 2002 | | .05 |
| 2003 | | .05 |
| 2004 | | .06 |
| 2005 | | .13 |
| 2006 | | .11 |
| 2007 | | .49 |
| 2008 | | .06 |
| 2009 | | .06 |
| 2010 | | .11 |
|
|