| Value | Category | Cases | |
|---|---|---|---|
| 2008 | 4 |
0.3%
|
|
| 2009 | 244 |
16.6%
|
|
| 2010 | 1217 |
83%
|
|
| 2011 | 2 |
0.1%
|
|
| Sysmiss | 1738 |