| Value | Category | Cases | |
|---|---|---|---|
| -1 | Missing | 0 | 
                                    
                                    0%
                                 | 
| 1 | Impassable | 0 | 
                                    
                                    0%
                                 | 
| 2 | Very poor | 216 | 
                                    
                                    18%
                                 | 
| 3 | Poor | 336 | 
                                    
                                    28%
                                 | 
| 4 | Fair | 432 | 
                                    
                                    36%
                                 | 
| 5 | Good | 200 | 
                                    
                                    16.7%
                                 | 
| 6 | Very good | 16 | 
                                    
                                    1.3%
                                 | 
| 7 | Not applicable | 0 | 
                                    
                                    0%
                                 |