| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 5 |
12.5%
|
| 0 | 9 |
22.5%
|
|
| 1 | 12 |
30%
|
|
| 2 | 3 |
7.5%
|
|
| 3 | 2 |
5%
|
|
| 5 | 1 |
2.5%
|
|
| 6 | 1 |
2.5%
|
|
| 10 | 2 |
5%
|
|
| 15 | 1 |
2.5%
|
|
| 19 | 1 |
2.5%
|
|
| 20 | 3 |
7.5%
|
|
| Sysmiss | 112 |