| Value | Category | Cases | |
|---|---|---|---|
| 1 | GPS | 6 | 
                                                                 
                                    
                                    3.6%
                                 
                                                             | 
                                                        
                    
| 2 | land title | 54 | 
                                                                 
                                    
                                    32.5%
                                 
                                                             | 
                                                        
                    
| 3 | self-reported | 106 | 
                                                                 
                                    
                                    63.9%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 334 |