| Value | Category | Cases | |
|---|---|---|---|
| 1 | monthly | 3 |
8.3%
|
| 2 | 3 months | 1 |
2.8%
|
| 3 | 6 months | 3 |
8.3%
|
| 4 | year | 29 |
80.6%
|
| Sysmiss | 16394 |