| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 | 
                                    
                                    0%
                                 | 
| 1 | Airport | 2 | 
                                    
                                    2.4%
                                 | 
| 2 | Land border crossing | 78 | 
                                    
                                    92.9%
                                 | 
| 3 | Seaport or waterway | 4 | 
                                    
                                    4.8%
                                 | 
| Sysmiss | 279 |