|
| year | production | consumption |
| 1984 | | |
| 1985 | | |
| 1986 | .49 | 1.60 |
| 1987 | 1.45 | 3.43 |
| 1988 | 1.82 | 3.45 |
| 1989 | .94 | 3.15 |
| 1990 | 1.38 | 3.04 |
| 1991 | 1.57 | 2.79 |
| 1992 | .92 | 3.16 |
| 1993 | .96 | 3.25 |
| 1994 | .98 | 3.33 |
| 1995 | .98 | 3.33 |
| 1996 | .98 | 3.32 |
| 1997 | 1.02 | 3.39 |
| 1998 | 1.02 | 3.39 |
| 1999 | 1.02 | 3.39 |
| 2000 | 1.06 | 4.91 |
| 2001 | 1.11 | 5.74 |
| 2002 | 1.13 | 6.07 |
| 2003 | 1.17 | 6.17 |
| 2004 | 1.16 | 8.50 |
| 2005 | 1.27 | 6.56 |
| 2006 | | 9.05 |
| 2007 | | 8.69 |
| 2008 | | 7.48 |
| 2009 | | 6.80 |
| 2010 | | 6.83 |
|
|
