|
| year | production | consumption |
| 1984 | | |
| 1985 | | |
| 1986 | 3.76 | 2.66 |
| 1987 | 4.48 | 3.11 |
| 1988 | 3.95 | 4.58 |
| 1989 | 5.22 | 4.38 |
| 1990 | 3.83 | 3.17 |
| 1991 | 3.13 | 3.17 |
| 1992 | 4.58 | 3.36 |
| 1993 | 4.90 | 3.79 |
| 1994 | 4.18 | 3.47 |
| 1995 | 5.76 | 4.87 |
| 1996 | 5.65 | 4.01 |
| 1997 | 6.09 | 4.51 |
| 1998 | .47 | 4.21 |
| 1999 | | 6.62 |
| 2000 | .01 | 4.11 |
| 2001 | 3.04 | 4.14 |
| 2002 | 4.50 | 2.65 |
| 2003 | 4.23 | 4.28 |
| 2004 | 4.65 | 3.01 |
| 2005 | 4.09 | 3.07 |
| 2006 | 5.60 | 3.83 |
| 2007 | 6.06 | 3.92 |
| 2008 | 3.78 | 4.87 |
| 2009 | 1.81 | 2.96 |
| 2010 | 3.84 | 3.24 |
|
|
