| Value | Category | Cases | |
|---|---|---|---|
| 1 | Self-produced | 4121 | 
                                    
                                    9.5%
                                 | 
| 2 | Purchased | 39395 | 
                                    
                                    90.5%
                                 | 
| 3 | Received for free | 6 | 
                                    
                                    0%
                                 | 
| Sysmiss | 783 |