| Value | 
                    Category | 
                                                                            
                                    
                    
                        | 1 | 
                        1994  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 2 | 
                        1995  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 3 | 
                        1996  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 4 | 
                        1997  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 5 | 
                        1998  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 6 | 
                        1999  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 7 | 
                        2000  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 8 | 
                        2001  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 9 | 
                        2002  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 10 | 
                        2003  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 11 | 
                        2004  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 12 | 
                        2005  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 13 | 
                        2006  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 14 | 
                        2007  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 15 | 
                        2008  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 16 | 
                        2009  | 
                        
                            
                        
                        
                        
                        
                            
                    
                                    
                    
                        | 17 | 
                        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.