| Value | Category | Cases | |
|---|---|---|---|
| -99 | 12 |
6.6%
|
|
| 1 | Every few days | 2 |
1.1%
|
| 2 | Every few weeks | 5 |
2.7%
|
| 3 | Every few months | 22 |
12%
|
| 4 | Not at all | 114 |
62.3%
|
| Sysmiss | 28 |
15.3%
|