| Value | Category | Cases | |
|---|---|---|---|
| -99 | 4 |
2.5%
|
|
| 1 | Every few days | 9 |
5.7%
|
| 2 | Every few weeks | 16 |
10.1%
|
| 3 | Every few months | 48 |
30.4%
|
| 4 | Not at all | 61 |
38.6%
|
| Sysmiss | 20 |
12.7%
|