| Value | Category | Cases | |
|---|---|---|---|
| 18 | 1 |
14.3%
|
|
| 20 | 1 |
14.3%
|
|
| 21 | 2 |
28.6%
|
|
| 22 | 1 |
14.3%
|
|
| 99 | 99. don't know | 2 |
28.6%
|
| Sysmiss | 92 |