| Value | Category | Cases | |
|---|---|---|---|
| 1990 | 1 |
1%
|
|
| 1995 | 6 |
6.2%
|
|
| 1996 | 6 |
6.2%
|
|
| 1997 | 4 |
4.1%
|
|
| 1998 | 4 |
4.1%
|
|
| 1999 | 1 |
1%
|
|
| 2000 | 3 |
3.1%
|
|
| 2001 | 3 |
3.1%
|
|
| 2002 | 1 |
1%
|
|
| 2003 | 6 |
6.2%
|
|
| 2004 | 3 |
3.1%
|
|
| 2005 | 23 |
23.7%
|
|
| 2006 | 14 |
14.4%
|
|
| 2007 | 15 |
15.5%
|
|
| 2008 | 4 |
4.1%
|
|
| n/a | 3 |
3.1%
|