| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| 10 | 1 |
2.3%
|
|
| 20 | 12 |
27.9%
|
|
| 30 | 11 |
25.6%
|
|
| 40 | 4 |
9.3%
|
|
| 50 | 10 |
23.3%
|
|
| 60 | 1 |
2.3%
|
|
| 70 | 2 |
4.7%
|
|
| 80 | 2 |
4.7%
|
|
| Sysmiss | 529 |