| Value | Category | Cases | |
|---|---|---|---|
| 1 | Every 2 months | 10 |
1.9%
|
| 2 | Every 3 months | 4 |
0.8%
|
| 3 | Every month | 475 |
89.6%
|
| 4 | Every six months | 4 |
0.8%
|
| 5 | Once a year (every 12 months) | 35 |
6.6%
|
| 6 | Other | 2 |
0.4%
|
| Sysmiss | 62 |