| Value | Category | Cases | |
|---|---|---|---|
| 2009 | 4 |
3.6%
|
|
| 2010 | 3 |
2.7%
|
|
| 2011 | 8 |
7.1%
|
|
| 2012 | 24 |
21.4%
|
|
| 2013 | 46 |
41.1%
|
|
| 2014 | 27 |
24.1%
|
|
| 9997 | Inconsistent | 0 |
0%
|
| 9998 | Don't know | 0 |
0%
|
| Sysmiss | 36318 |