| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 | 
                                                                 
                                    
                                    0.4%
                                 
                                                             | 
                                                        
                    
| 1 | Airport | 23 | 
                                                                 
                                    
                                    8.9%
                                 
                                                             | 
                                                        
                    
| 2 | Land border crossing | 48 | 
                                                                 
                                    
                                    18.7%
                                 
                                                             | 
                                                        
                    
| 3 | Seaport or waterway | 185 | 
                                                                 
                                    
                                    72%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 335 |