| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 |
4.7%
|
| 1 | Airport | 8 |
12.5%
|
| 2 | Land border crossing | 53 |
82.8%
|
| 3 | Seaport or waterway | 0 |
0%
|
| Sysmiss | 944 |