| Value | Category | Cases | |
|---|---|---|---|
| 1 | Are taken directly from establishment records | 607 | 
                                    
                                    63.6%
                                 | 
| 2 | Are estimates computed with some precision | 299 | 
                                    
                                    31.3%
                                 | 
| 3 | Are arbitrary and unreliable numbers | 15 | 
                                    
                                    1.6%
                                 | 
| 4 | Are in some case taken from books and in some case estimates | 34 | 
                                    
                                    3.6%
                                 |