| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
0.1%
|
| 1 | Annually | 13 |
1.3%
|
| 2 | Biannually/Every six months | 14 |
1.4%
|
| 3 | Quarterly | 51 |
4.9%
|
| 4 | Monthly | 911 |
87.9%
|
| 5 | Weekly | 16 |
1.5%
|
| 6 | Daily | 30 |
2.9%
|
| 7 | Hourly | 0 |
0%
|
| 8 | More than once in an hour | 0 |
0%
|
| Sysmiss | 203 |