| Value | Category |
|---|---|
| 1 | Not frequent enough |
| 2 | Stops are far away |
| 3 | No night service |
| 4 | Vehicles carriages are in bad condition |
| 5 | No schedule or schedule is not followed |
| 6 | Fares are too expensive |
| 7 | Too crowded |
| 8 | Too slow |
| 9 | Other |
| 10 | No problem |
| 11 | |
| 99 | Missing |
| Sysmiss |