| Value | Category | Cases | |
|---|---|---|---|
| -99 | 13 |
3.7%
|
|
| 1 | Every few days | 8 |
2.3%
|
| 2 | Every few weeks | 28 |
8%
|
| 3 | Every few months | 43 |
12.3%
|
| 4 | Not at all | 224 |
64.2%
|
| Sysmiss | 33 |
9.5%
|