| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 2 |
4.3%
|
| 1 | Airport | 6 |
12.8%
|
| 2 | Land border crossing | 7 |
14.9%
|
| 3 | Seaport or waterway | 32 |
68.1%
|
| Sysmiss | 1369 |