| Value | Category | Cases | |
|---|---|---|---|
| 2007 | 3 |
1.1%
|
|
| 2008 | 5 |
1.8%
|
|
| 2009 | 26 |
9.5%
|
|
| 2010 | 100 |
36.4%
|
|
| 2011 | 69 |
25.1%
|
|
| 9997 | Inconsistent (Secondary Editing) | 1 |
0.4%
|
| 9999 | Missing | 71 |
25.8%
|
| Sysmiss | 4552 |