| Value | Category | Cases | |
|---|---|---|---|
| 1 | NO DIFFICULTY | 5207 | 
                                    
                                    95%
                                 | 
| 2 | SOME DIFFICULTY | 98 | 
                                    
                                    1.8%
                                 | 
| 3 | A LOT OF DIFFICULTY | 11 | 
                                    
                                    0.2%
                                 | 
| 4 | CANNOT SEE AT ALL | 5 | 
                                    
                                    0.1%
                                 | 
| 9 | NO RESPONSE | 1 | 
                                    
                                    0%
                                 | 
| Sysmiss | 157 | 
                                    
                                    2.9%
                                 |