| Value | Category | Cases | |
|---|---|---|---|
| -999 | Don't know | 0 | 
                                    
                                    0%
                                 | 
| -888 | Not available | 0 | 
                                    
                                    0%
                                 | 
| 1 | Small scale | 27 | 
                                    
                                    56.3%
                                 | 
| 2 | Big scale | 21 | 
                                    
                                    43.8%
                                 |