|
| year | production | consumption |
| 1984 | 46.06 | 56.56 |
| 1985 | 48.06 | 56.25 |
| 1986 | 48.55 | 57.02 |
| 1987 | 53.80 | 57.96 |
| 1988 | 54.90 | 59.10 |
| 1989 | 54.43 | 60.10 |
| 1990 | 60.82 | 59.06 |
| 1991 | 55.72 | 64.61 |
| 1992 | 57.05 | 61.80 |
| 1993 | 53.99 | 59.50 |
| 1994 | 58.32 | 57.44 |
| 1995 | 52.83 | 55.40 |
| 1996 | 53.08 | 51.25 |
| 1997 | 55.82 | 48.73 |
| 1998 | 49.96 | 51.02 |
| 1999 | 49.59 | 47.58 |
| 2000 | 41.88 | 45.73 |
| 2001 | 47.04 | 46.07 |
| 2002 | 48.43 | 49.66 |
| 2003 | 45.58 | 50.84 |
| 2004 | 44.47 | 49.87 |
| 2005 | 45.49 | 48.11 |
| 2006 | 40.28 | 46.46 |
| 2007 | 42.85 | 45.05 |
| 2008 | 42.55 | 40.40 |
| 2009 | 42.16 | 42.69 |
| 2010 | 37.92 | 42.18 |
|
|