| Value | Category | Cases | |
|---|---|---|---|
| -1 | Missing | 0 | 
                                    
                                    0%
                                 | 
| 1 | Impassable | 88 | 
                                    
                                    7.3%
                                 | 
| 2 | Very poor | 376 | 
                                    
                                    31.3%
                                 | 
| 3 | Poor | 216 | 
                                    
                                    18%
                                 | 
| 4 | Fair | 248 | 
                                    
                                    20.7%
                                 | 
| 5 | Good | 232 | 
                                    
                                    19.3%
                                 | 
| 6 | Very good | 40 | 
                                    
                                    3.3%
                                 |