| Value | Category | Cases | |
|---|---|---|---|
| 2007 | 3 |
0.2%
|
|
| 2008 | 115 |
9.5%
|
|
| 2009 | 322 |
26.7%
|
|
| 2010 | 414 |
34.3%
|
|
| 2011 | 349 |
28.9%
|
|
| 2012 | 5 |
0.4%
|
|
| 9999 | Missing | 0 |
0%
|
| Sysmiss | 1124 |