|
| year | production | consumption |
| 1980 | | |
| 1981 | | |
| 1982 | | |
| 1983 | | |
| 1984 | | |
| 1985 | | |
| 1986 | | |
| 1987 | | |
| 1988 | | |
| 1989 | | |
| 1990 | | 15.00 |
| 1991 | | 6.90 |
| 1992 | | 7.03 |
| 1993 | | 8.67 |
| 1994 | | 8.37 |
| 1995 | | 8.37 |
| 1996 | | 8.83 |
| 1997 | | 9.37 |
| 1998 | | 10.07 |
| 1999 | | 11.86 |
| 2000 | | 12.63 |
| 2001 | | 15.05 |
| 2002 | | 15.42 |
| 2003 | | 16.64 |
| 2004 | | 17.58 |
| 2005 | | 17.75 |
| 2006 | | 19.12 |
| 2007 | | 20.11 |
| 2008 | | 20.39 |
| 2009 | | 21.99 |
| 2010 | | 20.81 |
| 2011 | | 26.00 |
|
|