|
| year | production | change |
| 1980 | 4.03 | NA |
| 1981 | 2.57 | -36.12 % |
| 1982 | 2.61 | 1.53 % |
| 1983 | 2.52 | -3.44 % |
| 1984 | 2.53 | 0.11 % |
| 1985 | 2.46 | -2.54 % |
| 1986 | 2.43 | -1.12 % |
| 1987 | 2.29 | -5.76 % |
| 1988 | 2.73 | 19.19 % |
| 1989 | 2.70 | -1.21 % |
| 1990 | 3.18 | 17.83 % |
| 1991 | 3.43 | 7.80 % |
| 1992 | 3.34 | -2.60 % |
| 1993 | 3.17 | -5.18 % |
| 1994 | 3.21 | 1.14 % |
| 1995 | 3.23 | 0.71 % |
| 1996 | 3.28 | 1.50 % |
| 1997 | 3.39 | 3.35 % |
| 1998 | 3.26 | -3.71 % |
| 1999 | 3.07 | -5.91 % |
| 2000 | 3.30 | 7.50 % |
| 2001 | 3.21 | -2.74 % |
| 2002 | 3.11 | -2.97 % |
| 2003 | 3.30 | 6.07 % |
| 2004 | 3.61 | 9.33 % |
| 2005 | 3.99 | 10.57 % |
| 2006 | 4.22 | 5.83 % |
| 2007 | 4.37 | 3.38 % |
| 2008 | 4.46 | 2.26 % |
| 2009 | 4.27 | -4.29 % |
| 2010 | 4.31 | 0.77 % |
|
|