| Value | Category | Cases | |
|---|---|---|---|
| 1 | 4 or less hours | 89 |
10.7%
|
| 2 | 5 hours | 96 |
11.6%
|
| 3 | 6 hours | 113 |
13.6%
|
| 4 | 7 hours | 134 |
16.2%
|
| 5 | 8 hours | 198 |
23.9%
|
| 6 | 9 hours | 93 |
11.2%
|
| 7 | 10 hours | 58 |
7%
|
| 8 | 11 or more hours | 48 |
5.8%
|
| Sysmiss | 90 |