| Value | Category | Cases | |
|---|---|---|---|
| 1 | monthly | 143 |
6.4%
|
| 2 | uarterly | 76 |
3.4%
|
| 3 | annually | 109 |
4.9%
|
| 4 | not regular | 1915 |
85.4%
|
| Sysmiss | 88 |