| Value | Category | Cases | |
|---|---|---|---|
| -9 | 1 | 
                                
                                0.1%
                             | |
| 1 | Now | 16 | 
                                
                                1%
                             | 
| 2 | Later | 34 | 
                                
                                2%
                             | 
| 3 | Not at all | 8 | 
                                
                                0.5%
                             | 
| 5 | Missing | 1 | 
                                
                                0.1%
                             | 
| 7 | Refusal | 0 | 
                                
                                0%
                             | 
| 9 | Not applicable | 1613 | 
                                
                                96.4%
                             |