|
| year | production | consumption |
| 1980 | | 30.86 |
| 1981 | | 50.71 |
| 1982 | | 52.91 |
| 1983 | | 76.06 |
| 1984 | | 105.82 |
| 1985 | | 113.54 |
| 1986 | | 125.66 |
| 1987 | | 101.41 |
| 1988 | | 103.62 |
| 1989 | | 108.03 |
| 1990 | | 104.72 |
| 1991 | | 106.92 |
| 1992 | | 74.96 |
| 1993 | | 74.96 |
| 1994 | | 112.44 |
| 1995 | | 91.49 |
| 1996 | | 106.92 |
| 1997 | | 93.70 |
| 1998 | | 110.23 |
| 1999 | | 95.90 |
| 2000 | | 163.14 |
| 2001 | | 154.32 |
| 2002 | | 160.94 |
| 2003 | | 152.12 |
| 2004 | | 171.96 |
| 2005 | | 165.35 |
| 2006 | | 147.71 |
| 2007 | | 177.47 |
| 2008 | | 155.43 |
| 2009 | | 142.20 |
| 2010 | | 149.91 |
| 2011 | | 146.61 |
|
|