| Value | Category | Cases | |
|---|---|---|---|
| 0 | not given | 954 | 
                                    
                                    46.6%
                                 | 
| 1995 | 37 | 
                                    
                                    1.8%
                                 | |
| 1996 | 67 | 
                                    
                                    3.3%
                                 | |
| 1997 | 113 | 
                                    
                                    5.5%
                                 | |
| 1998 | 165 | 
                                    
                                    8.1%
                                 | |
| 1999 | 376 | 
                                    
                                    18.4%
                                 | |
| 2000 | 181 | 
                                    
                                    8.8%
                                 | |
| 4444 | marked on card | 99 | 
                                    
                                    4.8%
                                 | 
| 6666 | mother reported | 55 | 
                                    
                                    2.7%
                                 | 
| 9997 | inconsistent | 0 | 
                                    
                                    0%
                                 | 
| 9998 | dk | 0 | 
                                    
                                    0%
                                 | 
| 9999 | missing | 0 | 
                                    
                                    0%
                                 | 
| Sysmiss | 13304 |