| Value | Category | Cases | |
|---|---|---|---|
| -9 | 2 | 
                                
                                0.1%
                             | |
| 1 | Now | 29 | 
                                
                                1.2%
                             | 
| 2 | Later | 40 | 
                                
                                1.7%
                             | 
| 3 | Not at all | 18 | 
                                
                                0.7%
                             | 
| 5 | Missing | 0 | 
                                
                                0%
                             | 
| 7 | Refusal | 0 | 
                                
                                0%
                             | 
| 9 | Not applicable | 2324 | 
                                
                                96.3%
                             |