| Value | Category | Cases | |
|---|---|---|---|
| 1988 | 1 |
16.7%
|
|
| 1990 | 1 |
16.7%
|
|
| 2000 | 2 |
33.3%
|
|
| 2001 | 2 |
33.3%
|
|
| Sysmiss | 4154 |