| Value | Category | 
                                    
                    
                        | 1 | JULY-SEPT 2009 | 
                                    
                    
                        | 2 | OCT-DEC 2009 | 
                                    
                    
                        | 3 | JAN-MARCH 2010 | 
                                    
                    
                        | 4 | APRIL-JUNE 2010 | 
                                    
                    
                        | 5 | JULY-SEPT 2010 | 
                                    
                    
                        | Sysmiss |  | 
                            
            Warning: these figures indicate the number of cases found in the data file. They cannot be interpreted as summary statistics of the population of interest.