| Value | Category | Cases | |
|---|---|---|---|
| 1 | Voluntary | 41 |
10.9%
|
| 2 | Paid overtime | 32 |
8.5%
|
| 3 | Part of main work | 216 |
57.6%
|
| 4 | An obligation without compensation | 73 |
19.5%
|
| 5 | Other | 13 |
3.5%
|
| 0 | NR | 104 | |
| 9 | NA | 1685 | |
| Sysmiss | 836 |