| Value | Category | Cases | |
|---|---|---|---|
| 0 | none | 2997 | 
                                    
                                    20.1%
                                 | 
| 1 | primary inc (< 7) | 4227 | 
                                    
                                    28.3%
                                 | 
| 2 | primary complete (7) | 1846 | 
                                    
                                    12.4%
                                 | 
| 3 | secy incomplete (8-11) | 4548 | 
                                    
                                    30.4%
                                 | 
| 4 | secy complete (12)/higher | 1328 | 
                                    
                                    8.9%
                                 |