| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
0.2%
|
| 1 | Annually | 11 |
2.2%
|
| 2 | Biannually/Every six months | 6 |
1.2%
|
| 3 | Quarterly | 28 |
5.6%
|
| 4 | Monthly | 420 |
84.7%
|
| 5 | Weekly | 14 |
2.8%
|
| 6 | Daily | 16 |
3.2%
|
| 7 | Hourly | 0 |
0%
|
| 8 | More than once in an hour | 0 |
0%
|
| Sysmiss | 743 |