| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| 1 | Once a year | 15 |
83.3%
|
| 2 | Twice a year | 0 |
0%
|
| 3 | Every month | 3 |
16.7%
|
| 4 | More than 12 times a year | 0 |
0%
|
| Sysmiss | 117 |