|
| year | production | consumption |
| 1984 | | |
| 1985 | | |
| 1986 | 1.99 | 1.98 |
| 1987 | 1.96 | 1.85 |
| 1988 | 1.88 | 1.87 |
| 1989 | 1.89 | 1.90 |
| 1990 | 2.77 | 2.77 |
| 1991 | 1.83 | 1.83 |
| 1992 | 2.73 | 2.73 |
| 1993 | 1.84 | 1.84 |
| 1994 | 1.79 | 1.79 |
| 1995 | 1.84 | 1.84 |
| 1996 | 1.88 | 1.88 |
| 1997 | 1.88 | 1.88 |
| 1998 | 1.89 | 1.89 |
| 1999 | .81 | 1.65 |
| 2000 | .06 | 1.01 |
| 2001 | 1.27 | 1.16 |
| 2002 | 1.38 | 1.18 |
| 2003 | 1.48 | 1.23 |
| 2004 | 1.58 | 1.31 |
| 2005 | 1.70 | 2.03 |
| 2006 | 1.70 | 1.43 |
| 2007 | 1.73 | 1.35 |
| 2008 | 1.30 | 1.17 |
| 2009 | 1.44 | 1.37 |
| 2010 | 1.82 | 2.34 |
|
|