| Value | Category | Cases | |
|---|---|---|---|
| 0 | Not given | 4022 | 
                                                                 
                                    
                                    52%
                                 
                                                             | 
                                                        
                    
| 2001 | 1 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    |
| 2002 | 277 | 
                                                                 
                                    
                                    3.6%
                                 
                                                             | 
                                                        
                    |
| 2003 | 790 | 
                                                                 
                                    
                                    10.2%
                                 
                                                             | 
                                                        
                    |
| 2004 | 749 | 
                                                                 
                                    
                                    9.7%
                                 
                                                             | 
                                                        
                    |
| 2005 | 851 | 
                                                                 
                                    
                                    11%
                                 
                                                             | 
                                                        
                    |
| 2006 | 921 | 
                                                                 
                                    
                                    11.9%
                                 
                                                             | 
                                                        
                    |
| 2007 | 73 | 
                                                                 
                                    
                                    0.9%
                                 
                                                             | 
                                                        
                    |
| 4444 | Marked on card | 51 | 
                                                                 
                                    
                                    0.7%
                                 
                                                             | 
                                                        
                    
| 6666 | Mother reported | 0 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    
| 9997 | Inconsistent | 6 | 
                                                                 
                                    
                                    0.1%
                                 
                                                             | 
                                                        
                    
| 9998 | DK | 0 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    
| 9999 | Missing | 0 | 
                                                                 
                                    
                                    0%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 1054 |