| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 4 |
7.5%
|
| 1 | Airport | 16 |
30.2%
|
| 2 | Land border crossing | 0 |
0%
|
| 3 | Seaport | 33 |
62.3%
|
| Sysmiss | 300 |