| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 33 |
12.1%
|
| 0 | None | 165 |
60.4%
|
| 1 | 40 |
14.7%
|
|
| 2 | 11 |
4%
|
|
| 3 | 5 |
1.8%
|
|
| 5 | 9 |
3.3%
|
|
| 6 | 1 |
0.4%
|
|
| 8 | 1 |
0.4%
|
|
| 10 | 3 |
1.1%
|
|
| 15 | 4 |
1.5%
|
|
| 20 | 1 |
0.4%
|
|
| Sysmiss | 319 |