| Value | Category | Cases | |
|---|---|---|---|
| 0 | not given | 93 | 
                                    
                                    4.5%
                                 | 
| 1995 | 65 | 
                                    
                                    3.2%
                                 | |
| 1996 | 123 | 
                                    
                                    6%
                                 | |
| 1997 | 191 | 
                                    
                                    9.3%
                                 | |
| 1998 | 349 | 
                                    
                                    17%
                                 | |
| 1999 | 728 | 
                                    
                                    35.6%
                                 | |
| 2000 | 394 | 
                                    
                                    19.2%
                                 | |
| 4444 | marked on card | 76 | 
                                    
                                    3.7%
                                 | 
| 6666 | mother reported | 27 | 
                                    
                                    1.3%
                                 | 
| 9997 | inconsistent | 0 | 
                                    
                                    0%
                                 | 
| 9998 | dk | 0 | 
                                    
                                    0%
                                 | 
| 9999 | missing | 1 | 
                                    
                                    0%
                                 | 
| Sysmiss | 13304 |