| Value | Category | Cases | |
|---|---|---|---|
| 2000 | 1 |
0.4%
|
|
| 2003 | 4 |
1.7%
|
|
| 2006 | 2 |
0.9%
|
|
| 2007 | 15 |
6.4%
|
|
| 2008 | 211 |
90.6%
|
|
| Sysmiss | 4146 |