| Value | Category | Cases | |
|---|---|---|---|
| -99 | 9 |
6.1%
|
|
| 1 | Every few days | 13 |
8.8%
|
| 2 | Every few weeks | 29 |
19.7%
|
| 3 | Every few months | 56 |
38.1%
|
| 4 | Not at all | 16 |
10.9%
|
| Sysmiss | 24 |
16.3%
|