| Value | Category | Cases | |
|---|---|---|---|
| 1 | monthly | 563 |
7.5%
|
| 2 | every few months | 908 |
12%
|
| 3 | somthing else | 200 |
2.7%
|
| 4 | no | 4128 |
54.7%
|
| Sysmiss | 1741 |