| Value | Category | Cases | |
|---|---|---|---|
| 1994 | 1 |
12.5%
|
|
| 2002 | 1 |
12.5%
|
|
| 2006 | 2 |
25%
|
|
| 2010 | 2 |
25%
|
|
| 2011 | 2 |
25%
|
|
| Sysmiss | 453 |