| Value | Category | Cases | |
|---|---|---|---|
| 2007 | 40 |
9.3%
|
|
| 2008 | 80 |
18.6%
|
|
| 2009 | 96 |
22.4%
|
|
| 2010 | 73 |
17%
|
|
| 2011 | 97 |
22.6%
|
|
| 2012 | 43 |
10%
|
|
| 9997 | Inconsistent | 0 |
0%
|
| 9999 | Missing | 0 |
0%
|
| Sysmiss | 4 |