| Year | Volume | Number | Holdings | ||
|---|---|---|---|---|---|
| 2007 | 41 | 4 | Yes | ||
| 2007 | 41 | 3 | Yes | ||
| 2007 | 41 | 1 -2 | Yes | ||
| 2005/2006 | 40 | 1 -4 | Yes | ||
| 2004 | 39 | 1 -4 | Yes | ||
| 2003 | 38 | 1 -4 | Yes | ||
| 2002 | 37 | 3 -4 | Yes | ||
| 2002 | 37 | 2 | No | ||
| 2002 | 37 | 1 | Yes | ||
| 2001 | 36 | 1 -4 | Yes | ||
| 2000 | 35 | 1 -4 | Yes | ||
| 1999 | 34 | 1 -4 | Yes | ||
| 1998 | 33 | 1 -4 | Yes | ||
| 1997 | 32 | 1 -4 | Yes | ||
| 1996 | 31 | 1 -4 | Yes | ||
| 1995 | 30 | 1 -4 | No | ||
| 1994 | 29 | 1 -4 | Yes | ||
| 1993 | 28 | 1 -4 | Yes | ||
| 1992 | 27 | 1 -4 | Yes | ||
| 1991 | 26 | 1 -4 | Yes | ||
| 1990 | 26 | 4 | Yes |