| Value | Category | Cases | |
|---|---|---|---|
| -99 | 12 |
6.6%
|
|
| 1 | Every few days | 3 |
1.6%
|
| 2 | Every few weeks | 14 |
7.7%
|
| 3 | Every few months | 31 |
16.9%
|
| 4 | Not at all | 95 |
51.9%
|
| Sysmiss | 28 |
15.3%
|