| Value | Category | Cases | |
|---|---|---|---|
| 1 | Once every two weeks | 569 |
18.4%
|
| 2 | Once every month | 544 |
17.6%
|
| 3 | Once every three months | 1279 |
41.4%
|
| 4 | Once every six months | 554 |
17.9%
|
| 5 | Once a year | 141 |
4.6%
|
| Sysmiss | 11 |