| Value | Category | Cases | |
|---|---|---|---|
| -99 | 8 |
2.4%
|
|
| 1 | Every few days | 10 |
3%
|
| 2 | Every few weeks | 35 |
10.4%
|
| 3 | Every few months | 169 |
50.4%
|
| 4 | Not at all | 63 |
18.8%
|
| Sysmiss | 50 |
14.9%
|