| Value | Category | Cases | |
|---|---|---|---|
| 1 | Flat | 231 | 
                                    
                                    72%
                                 | 
| 2 | Slight slope | 72 | 
                                    
                                    22.4%
                                 | 
| 3 | Moderate slope | 16 | 
                                    
                                    5%
                                 | 
| 4 | Steep, hilly | 2 | 
                                    
                                    0.6%
                                 | 
| Sysmiss | 140 |