| Value | Category | Cases | |
|---|---|---|---|
| 1 | None | 146 |
16%
|
| 2 | Less than 6 hours | 157 |
17.2%
|
| 3 | 6–15 hours | 238 |
26.1%
|
| 4 | 16–35 hours | 151 |
16.6%
|
| 5 | More than 35 hours | 219 |
24%
|
| Sysmiss | 89 |