|
| year | production | consumption |
| 1980 | | 491.63 |
| 1981 | | 741.86 |
| 1982 | | 666.90 |
| 1983 | | 579.82 |
| 1984 | | 799.18 |
| 1985 | | 795.87 |
| 1986 | | 693.35 |
| 1987 | | 642.65 |
| 1988 | | 552.26 |
| 1989 | | 572.10 |
| 1990 | | 586.43 |
| 1991 | | 493.84 |
| 1992 | | 346.13 |
| 1993 | | 287.70 |
| 1994 | | 291.01 |
| 1995 | | 311.95 |
| 1996 | | 234.79 |
| 1997 | | 180.78 |
| 1998 | | 149.91 |
| 1999 | | 157.63 |
| 2000 | | 227.08 |
| 2001 | | 243.61 |
| 2002 | | 224.87 |
| 2003 | | 231.49 |
| 2004 | | 221.56 |
| 2005 | | 261.25 |
| 2006 | | 271.17 |
| 2007 | | 318.57 |
| 2008 | | 287.70 |
| 2009 | | 267.86 |
| 2010 | | 271.17 |
| 2011 | | 278.88 |
|
|