|
| year | production | consumption |
| 1980 | | 109.00 |
| 1981 | | 100.00 |
| 1982 | | 95.00 |
| 1983 | | 89.00 |
| 1984 | | 85.00 |
| 1985 | | 70.70 |
| 1986 | | 69.20 |
| 1987 | | 69.62 |
| 1988 | | 64.82 |
| 1989 | | 68.67 |
| 1990 | | 67.00 |
| 1991 | | 63.52 |
| 1992 | | 62.73 |
| 1993 | | 63.06 |
| 1994 | | 65.91 |
| 1995 | | 69.47 |
| 1996 | | 69.29 |
| 1997 | | 73.73 |
| 1998 | | 73.66 |
| 1999 | | 71.18 |
| 2000 | | 70.96 |
| 2001 | | 71.86 |
| 2002 | | 70.51 |
| 2003 | | 65.76 |
| 2004 | | 66.39 |
| 2005 | | 69.94 |
| 2006 | | 73.14 |
| 2007 | | 75.63 |
| 2008 | | 87.09 |
| 2009 | | 79.04 |
| 2010 | | 74.80 |
| 2011 | | 70.00 |
|
|