| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 2 |
8%
|
| 1 | Airport | 0 |
0%
|
| 2 | Land border crossing | 17 |
68%
|
| 3 | Seaport or waterway | 6 |
24%
|
| Sysmiss | 338 |