| Value | Category | Cases | |
|---|---|---|---|
| 1 | once per month | 1309 |
6.7%
|
| 2 | once every few months | 1165 |
6%
|
| 3 | other | 330 |
1.7%
|
| 4 | no | 5503 |
28.2%
|
| Sysmiss | 11202 |