| Value | Category | Cases | |
|---|---|---|---|
| 2005 | 4 |
14.3%
|
|
| 2006 | 13 |
46.4%
|
|
| 2007 | 9 |
32.1%
|
|
| 2008 | 1 |
3.6%
|
|
| 9997 | inconsistent | 1 |
3.6%
|
| 9998 | dk | 0 |
0%
|
| 10001 | .Z | 18726 |