| Year | Volume | Number | Holdings | ||
|---|---|---|---|---|---|
| 2013 | 12 | 1 | Yes | ||
| 2012 | 11 | 2 | Yes | ||
| 2012 | 11 | 1 | Yes | ||
| 2011 | 10 | 2 | Yes | ||
| 2011 | 10 | 1 | Yes | ||
| 2010 | 9 | 1 /2 | Yes | ||
| 2009 | 8 | 2 | Yes | ||
| 2009 | 8 | 1 | Yes | ||
| 2008 | 7 | 2 | Yes | ||
| 2008 | 7 | 1 | Yes | ||
| 2005 | 6 | 2 | Yes | ||
| 2005 | 6 | 1 | Yes | ||
| 2004 | 5 | 2 | Yes | ||
| 2004 | 5 | 1 | Yes | ||
| 2003 | 4 | 2 | Yes | ||
| 2003 | 4 | 1 | Yes | ||
| 2002 | 3 | 2 | Yes | ||
| 2002 | 3 | 1 | Yes | ||
| 2001 | 2 | 2 | Yes | ||
| 2001 | 2 | 1 | Yes | ||
| 2000 | 1 | 2 | Yes | ||
| 1999 | 1 | 1 | Yes |