| Value | Category | Cases | |
|---|---|---|---|
| 2005 | 1 |
20%
|
|
| 2009 | 1 |
20%
|
|
| 2010 | 1 |
20%
|
|
| 2013 | 1 |
20%
|
|
| 2015 | 1 |
20%
|
|
| 9998 | don't know | 0 |
0%
|
| Sysmiss | 12910 |