| Value | Category | Cases | |
|---|---|---|---|
| 2007 | 199 |
6.6%
|
|
| 2008 | 674 |
22.5%
|
|
| 2009 | 605 |
20.2%
|
|
| 2010 | 588 |
19.6%
|
|
| 2011 | 565 |
18.9%
|
|
| 2012 | 366 |
12.2%
|
|
| 9997 | Inconsistent | 0 |
0%
|
| 9999 | Missing | 0 |
0%
|
| Sysmiss | 133 |