| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 | 
                                    
                                    1.1%
                                 | 
| 1 | 1-2 production performance indicators | 33 | 
                                    
                                    12%
                                 | 
| 2 | 3-9 production performance indicators | 146 | 
                                    
                                    53.3%
                                 | 
| 3 | 10 or more production performance indicators | 92 | 
                                    
                                    33.6%
                                 | 
| Sysmiss | 338 |