| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
2.1%
|
| 1 | Annually | 19 |
39.6%
|
| 2 | Biannually/Every six months | 3 |
6.3%
|
| 3 | Quarterly | 11 |
22.9%
|
| 4 | Monthly | 10 |
20.8%
|
| 5 | Weekly | 1 |
2.1%
|
| 6 | Daily | 3 |
6.3%
|
| 7 | Hourly | 0 |
0%
|
| 8 | More than once in an hour | 0 |
0%
|
| Sysmiss | 1321 |