| Value | Category | Cases | |
|---|---|---|---|
| -1 | Missing | 0 |
0%
|
| 1 | State-owned airlines only | 245 |
20.4%
|
| 2 | Private airlines only | 71 |
5.9%
|
| 3 | State and private airlines | 805 |
67.1%
|
| 8 | Refused | 9 |
0.8%
|
| 9 | Don't know | 70 |
5.8%
|