| Value | Category | Cases | |
|---|---|---|---|
| -99 | Don't know | 0 |
0%
|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| 10 | 3 |
10%
|
|
| 15 | 5 |
16.7%
|
|
| 20 | 8 |
26.7%
|
|
| 25 | 3 |
10%
|
|
| 30 | 8 |
26.7%
|
|
| 40 | 1 |
3.3%
|
|
| 50 | 1 |
3.3%
|
|
| 70 | 1 |
3.3%
|
|
| Sysmiss | 120 |