| Value | Category | Cases | |
|---|---|---|---|
| 1945 | 1 | 
                                                                 
                                    
                                    0.5%
                                 
                                                             | 
                                                        
                    |
| 1948 | 2 | 
                                                                 
                                    
                                    1%
                                 
                                                             | 
                                                        
                    |
| 1952 | 1 | 
                                                                 
                                    
                                    0.5%
                                 
                                                             | 
                                                        
                    |
| 1953 | 3 | 
                                                                 
                                    
                                    1.5%
                                 
                                                             | 
                                                        
                    |
| 1954 | 2 | 
                                                                 
                                    
                                    1%
                                 
                                                             | 
                                                        
                    |
| 1956 | 3 | 
                                                                 
                                    
                                    1.5%
                                 
                                                             | 
                                                        
                    |
| 1957 | 5 | 
                                                                 
                                    
                                    2.4%
                                 
                                                             | 
                                                        
                    |
| 1960 | 1 | 
                                                                 
                                    
                                    0.5%
                                 
                                                             | 
                                                        
                    |
| 1961 | 4 | 
                                                                 
                                    
                                    1.9%
                                 
                                                             | 
                                                        
                    |
| 1962 | 9 | 
                                                                 
                                    
                                    4.4%
                                 
                                                             | 
                                                        
                    |
| 1963 | 3 | 
                                                                 
                                    
                                    1.5%
                                 
                                                             | 
                                                        
                    |
| 1964 | 4 | 
                                                                 
                                    
                                    1.9%
                                 
                                                             | 
                                                        
                    |
| 1965 | 3 | 
                                                                 
                                    
                                    1.5%
                                 
                                                             | 
                                                        
                    |
| 1966 | 15 | 
                                                                 
                                    
                                    7.3%
                                 
                                                             | 
                                                        
                    |
| 1967 | 5 | 
                                                                 
                                    
                                    2.4%
                                 
                                                             | 
                                                        
                    |
| 1968 | 11 | 
                                                                 
                                    
                                    5.3%
                                 
                                                             | 
                                                        
                    |
| 1969 | 6 | 
                                                                 
                                    
                                    2.9%
                                 
                                                             | 
                                                        
                    |
| 1970 | 4 | 
                                                                 
                                    
                                    1.9%
                                 
                                                             | 
                                                        
                    |
| 1971 | 14 | 
                                                                 
                                    
                                    6.8%
                                 
                                                             | 
                                                        
                    |
| 1972 | 11 | 
                                                                 
                                    
                                    5.3%
                                 
                                                             | 
                                                        
                    |
| 1973 | 9 | 
                                                                 
                                    
                                    4.4%
                                 
                                                             | 
                                                        
                    |
| 1974 | 3 | 
                                                                 
                                    
                                    1.5%
                                 
                                                             | 
                                                        
                    |
| 1975 | 4 | 
                                                                 
                                    
                                    1.9%
                                 
                                                             | 
                                                        
                    |
| 1976 | 12 | 
                                                                 
                                    
                                    5.8%
                                 
                                                             | 
                                                        
                    |
| 1977 | 11 | 
                                                                 
                                    
                                    5.3%
                                 
                                                             | 
                                                        
                    |
| 1978 | 12 | 
                                                                 
                                    
                                    5.8%
                                 
                                                             | 
                                                        
                    |
| 1979 | 2 | 
                                                                 
                                    
                                    1%
                                 
                                                             | 
                                                        
                    |
| 1980 | 4 | 
                                                                 
                                    
                                    1.9%
                                 
                                                             | 
                                                        
                    |
| 1981 | 5 | 
                                                                 
                                    
                                    2.4%
                                 
                                                             | 
                                                        
                    |
| 1982 | 4 | 
                                                                 
                                    
                                    1.9%
                                 
                                                             | 
                                                        
                    |
| 1983 | 1 | 
                                                                 
                                    
                                    0.5%
                                 
                                                             | 
                                                        
                    |
| 1985 | 3 | 
                                                                 
                                    
                                    1.5%
                                 
                                                             | 
                                                        
                    |
| 1987 | 2 | 
                                                                 
                                    
                                    1%
                                 
                                                             | 
                                                        
                    |
| 1989 | 2 | 
                                                                 
                                    
                                    1%
                                 
                                                             | 
                                                        
                    |
| 1990 | 5 | 
                                                                 
                                    
                                    2.4%
                                 
                                                             | 
                                                        
                    |
| 1991 | 1 | 
                                                                 
                                    
                                    0.5%
                                 
                                                             | 
                                                        
                    |
| 1993 | 2 | 
                                                                 
                                    
                                    1%
                                 
                                                             | 
                                                        
                    |
| 1994 | 1 | 
                                                                 
                                    
                                    0.5%
                                 
                                                             | 
                                                        
                    |
| 1995 | 5 | 
                                                                 
                                    
                                    2.4%
                                 
                                                             | 
                                                        
                    |
| 1996 | 3 | 
                                                                 
                                    
                                    1.5%
                                 
                                                             | 
                                                        
                    |
| 1999 | 1 | 
                                                                 
                                    
                                    0.5%
                                 
                                                             | 
                                                        
                    |
| 9999 | 9999. Don't know | 7 | 
                                                                 
                                    
                                    3.4%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 793 |