| Value | Category | Cases | |
|---|---|---|---|
| 2004 | 1 |
0.2%
|
|
| 2006 | 45 |
9.1%
|
|
| 2007 | 247 |
49.8%
|
|
| 2008 | 203 |
40.9%
|
|
| Sysmiss | 126 |