|
| year | production | consumption |
| 1984 | | |
| 1985 | | |
| 1986 | 2.13 | 1.41 |
| 1987 | 2.04 | 2.04 |
| 1988 | 2.70 | .99 |
| 1989 | 5.18 | 2.73 |
| 1990 | 3.70 | 3.80 |
| 1991 | 3.97 | 3.52 |
| 1992 | 2.98 | 3.89 |
| 1993 | 4.63 | 4.35 |
| 1994 | 4.63 | 4.41 |
| 1995 | 4.65 | 4.41 |
| 1996 | 4.63 | 4.40 |
| 1997 | 4.67 | 4.41 |
| 1998 | 4.68 | 4.47 |
| 1999 | 4.87 | 4.62 |
| 2000 | | 4.62 |
| 2001 | | 2.23 |
| 2002 | | 2.24 |
| 2003 | | 2.37 |
| 2004 | | 2.51 |
| 2005 | | 2.66 |
| 2006 | | 2.79 |
| 2007 | | 3.17 |
| 2008 | | 3.39 |
| 2009 | | 3.58 |
| 2010 | | 3.81 |
|
|
