|
| year | production | consumption |
| 1984 | | |
| 1985 | | |
| 1986 | | .44 |
| 1987 | | .41 |
| 1988 | | .45 |
| 1989 | | .46 |
| 1990 | | .43 |
| 1991 | | .47 |
| 1992 | | .48 |
| 1993 | | .54 |
| 1994 | | .57 |
| 1995 | | .57 |
| 1996 | | .57 |
| 1997 | | .60 |
| 1998 | | .60 |
| 1999 | | .60 |
| 2000 | | .67 |
| 2001 | | .70 |
| 2002 | | .70 |
| 2003 | | .76 |
| 2004 | | .79 |
| 2005 | | .89 |
| 2006 | | .86 |
| 2007 | | .86 |
| 2008 | | .89 |
| 2009 | | .44 |
| 2010 | | .44 |
|
|